diff --git a/qa/rpc-tests/test_framework/authproxy.py b/qa/rpc-tests/test_framework/authproxy.py
index c3b3e7eb3..c36042e1d 100644
--- a/qa/rpc-tests/test_framework/authproxy.py
+++ b/qa/rpc-tests/test_framework/authproxy.py
@@ -34,18 +34,12 @@
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 """
 
-try:
-    import http.client as httplib
-except ImportError:
-    import httplib
+import http.client
 import base64
 import decimal
-import json
+from pyutil import jsonutil as json
 import logging
-try:
-    import urllib.parse as urlparse
-except ImportError:
-    import urlparse
+import urllib.parse
 
 USER_AGENT = "AuthServiceProxy/0.1"
 
@@ -59,22 +53,14 @@ class JSONRPCException(Exception):
         self.error = rpc_error
 
 
-def EncodeDecimal(o):
-    if isinstance(o, decimal.Decimal):
-        return round(o, 8)
-    raise TypeError(repr(o) + " is not JSON serializable")
-
-class AuthServiceProxy(object):
+class AuthServiceProxy():
     __id_count = 0
 
     def __init__(self, service_url, service_name=None, timeout=HTTP_TIMEOUT, connection=None):
         self.__service_url = service_url
         self.__service_name = service_name
-        self.__url = urlparse.urlparse(service_url)
-        if self.__url.port is None:
-            port = 80
-        else:
-            port = self.__url.port
+        self.__url = urllib.parse.urlparse(service_url)
+        
         (user, passwd) = (self.__url.username, self.__url.password)
         try:
             user = user.encode('utf8')
@@ -87,17 +73,21 @@ class AuthServiceProxy(object):
         authpair = user + b':' + passwd
         self.__auth_header = b'Basic ' + base64.b64encode(authpair)
 
-        if connection:
-            # Callables re-use the connection of the original proxy
-            self.__conn = connection
-        elif self.__url.scheme == 'https':
-            self.__conn = httplib.HTTPSConnection(self.__url.hostname, port,
-                                                  None, None, False,
-                                                  timeout)
-        else:
-            self.__conn = httplib.HTTPConnection(self.__url.hostname, port,
-                                                 False, timeout)
+        self.timeout = timeout
+        self._set_conn(connection)
 
+    def _set_conn(self, connection=None):
+        port = 80 if self.__url.port is None else self.__url.port
+        if connection:
+            self.__conn = connection
+            self.timeout = connection.timeout
+        elif self.__url.scheme == 'https':
+            self.__conn = http.client.HTTPSConnection(self.__url.hostname, port, timeout=self.timeout)
+        else:
+            self.__conn = http.client.HTTPConnection(self.__url.hostname, port, timeout=self.timeout)
+
+
+   
     def __getattr__(self, name):
         if name.startswith('__') and name.endswith('__'):
             # Python internal stuff
@@ -105,7 +95,7 @@ class AuthServiceProxy(object):
         if self.__service_name is not None:
             name = "%s.%s" % (self.__service_name, name)
         return AuthServiceProxy(self.__service_url, name, connection=self.__conn)
-
+   
     def _request(self, method, path, postdata):
         '''
         Do a HTTP request, with retry if we get disconnected (e.g. due to a timeout).
@@ -120,12 +110,10 @@ class AuthServiceProxy(object):
             return self._get_response()
         except Exception as e:
             # If connection was closed, try again.
-            # Python 2.7 error message was changed in https://github.com/python/cpython/pull/2825
             # Python 3.5+ raises BrokenPipeError instead of BadStatusLine when the connection was reset.
             # ConnectionResetError happens on FreeBSD with Python 3.4.
             # These classes don't exist in Python 2.x, so we can't refer to them directly.
-            if ((isinstance(e, httplib.BadStatusLine)
-                    and e.line in ("''", "No status line received - the server has closed the connection"))
+            if ((isinstance(e, http.client.BadStatusLine) and e.line == "''")
                 or e.__class__.__name__ in ('BrokenPipeError', 'ConnectionResetError')):
                 self.__conn.close()
                 self.__conn.request(method, path, postdata, headers)
@@ -137,11 +125,11 @@ class AuthServiceProxy(object):
         AuthServiceProxy.__id_count += 1
 
         log.debug("-%s-> %s %s"%(AuthServiceProxy.__id_count, self.__service_name,
-                                 json.dumps(args, default=EncodeDecimal)))
+                                 json.dumps(args)))
         postdata = json.dumps({'version': '1.1',
                                'method': self.__service_name,
                                'params': args,
-                               'id': AuthServiceProxy.__id_count}, default=EncodeDecimal)
+                               'id': AuthServiceProxy.__id_count})
         response = self._request('POST', self.__url.path, postdata)
         if response['error'] is not None:
             raise JSONRPCException(response['error'])
@@ -152,7 +140,7 @@ class AuthServiceProxy(object):
             return response['result']
 
     def _batch(self, rpc_call_list):
-        postdata = json.dumps(list(rpc_call_list), default=EncodeDecimal)
+        postdata = json.dumps(list(rpc_call_list))
         log.debug("--> "+postdata)
         return self._request('POST', self.__url.path, postdata)
 
@@ -165,7 +153,7 @@ class AuthServiceProxy(object):
         responsedata = http_response.read().decode('utf8')
         response = json.loads(responsedata, parse_float=decimal.Decimal)
         if "error" in response and response["error"] is None:
-            log.debug("<-%s- %s"%(response["id"], json.dumps(response["result"], default=EncodeDecimal)))
+            log.debug("<-%s- %s"%(response["id"], json.dumps(response["result"])))
         else:
             log.debug("<-- "+responsedata)
         return response
diff --git a/qa/rpc-tests/test_framework/bignum.py b/qa/rpc-tests/test_framework/bignum.py
index 29658d4c6..5c7c5e45b 100644
--- a/qa/rpc-tests/test_framework/bignum.py
+++ b/qa/rpc-tests/test_framework/bignum.py
@@ -10,8 +10,6 @@
 
 """Bignum routines"""
 
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 import struct
 
 
diff --git a/qa/rpc-tests/test_framework/blockstore.py b/qa/rpc-tests/test_framework/blockstore.py
index fc157f718..f3cea3d2c 100644
--- a/qa/rpc-tests/test_framework/blockstore.py
+++ b/qa/rpc-tests/test_framework/blockstore.py
@@ -6,12 +6,12 @@
 from mininode import CBlock, CBlockHeader, CBlockLocator, CTransaction, msg_block, msg_headers, msg_tx
 
 import sys
-import cStringIO
-import dbm
+import io
+import anydbm
 
-class BlockStore(object):
+class BlockStore():
     def __init__(self, datadir):
-        self.blockDB = dbm.open(datadir + "/blocks", 'c')
+        self.blockDB = anydbm.open(datadir + "/blocks", 'c')
         self.currentBlock = 0L
 
     def close(self):
@@ -23,7 +23,7 @@ class BlockStore(object):
             serialized_block = self.blockDB[repr(blockhash)]
         except KeyError:
             return None
-        f = cStringIO.StringIO(serialized_block)
+        f = io.StringIO(serialized_block)
         ret = CBlock()
         ret.deserialize(f)
         ret.calc_sha256()
@@ -62,7 +62,7 @@ class BlockStore(object):
         try:
             self.blockDB[repr(block.sha256)] = bytes(block.serialize())
         except TypeError as e:
-            print "Unexpected error: ", sys.exc_info()[0], e.args
+            print("Unexpected error: ", sys.exc_info()[0], e.args)
         self.currentBlock = block.sha256
 
     def get_blocks(self, inv):
@@ -96,7 +96,7 @@ class BlockStore(object):
 
 class TxStore(object):
     def __init__(self, datadir):
-        self.txDB = dbm.open(datadir + "/transactions", 'c')
+        self.txDB = anydbm.open(datadir + "/transactions", 'c')
 
     def close(self):
         self.txDB.close()
@@ -107,7 +107,7 @@ class TxStore(object):
             serialized_tx = self.txDB[repr(txhash)]
         except KeyError:
             return None
-        f = cStringIO.StringIO(serialized_tx)
+        f = io.StringIO(serialized_tx)
         ret = CTransaction()
         ret.deserialize(f)
         ret.calc_sha256()
@@ -118,7 +118,7 @@ class TxStore(object):
         try:
             self.txDB[repr(tx.sha256)] = bytes(tx.serialize())
         except TypeError as e:
-            print "Unexpected error: ", sys.exc_info()[0], e.args
+            print("Unexpected error: ", sys.exc_info()[0], e.args)
 
     def get_transactions(self, inv):
         responses = []
diff --git a/qa/rpc-tests/test_framework/comptool.py b/qa/rpc-tests/test_framework/comptool.py
index 153ded981..b51a01758 100755
--- a/qa/rpc-tests/test_framework/comptool.py
+++ b/qa/rpc-tests/test_framework/comptool.py
@@ -140,13 +140,13 @@ class TestNode(NodeConnCB):
 #    across all connections.  (If outcome of final tx is specified as true
 #    or false, then only the last tx is tested against outcome.)
 
-class TestInstance(object):
+class TestInstance():
     def __init__(self, objects=None, sync_every_block=True, sync_every_tx=False):
         self.blocks_and_transactions = objects if objects else []
         self.sync_every_block = sync_every_block
         self.sync_every_tx = sync_every_tx
 
-class TestManager(object):
+class TestManager():
 
     def __init__(self, testgen, datadir):
         self.test_generator = testgen
@@ -335,7 +335,7 @@ class TestManager(object):
                 if (not self.check_mempool(tx.sha256, tx_outcome)):
                     raise AssertionError("Mempool test failed at test %d" % test_number)
 
-            print "Test %d: PASS" % test_number, [ c.rpc.getblockcount() for c in self.connections ]
+            print("Test %d: PASS" % test_number, [ c.rpc.getblockcount() for c in self.connections ])
             test_number += 1
 
         [ c.disconnect_node() for c in self.connections ]
diff --git a/qa/rpc-tests/test_framework/equihash.py b/qa/rpc-tests/test_framework/equihash.py
index e40451978..f025095cd 100755
--- a/qa/rpc-tests/test_framework/equihash.py
+++ b/qa/rpc-tests/test_framework/equihash.py
@@ -24,7 +24,7 @@ def expand_array(inp, out_len, bit_len, byte_pad=0):
     acc_value = 0;
 
     j = 0
-    for i in xrange(len(inp)):
+    for i in range(len(inp)):
         acc_value = ((acc_value << 8) & word_mask) | inp[i]
         acc_bits += 8
 
@@ -32,7 +32,7 @@ def expand_array(inp, out_len, bit_len, byte_pad=0):
         # output element.
         if acc_bits >= bit_len:
             acc_bits -= bit_len
-            for x in xrange(byte_pad, out_width):
+            for x in range(byte_pad, out_width):
                 out[j+x] = (
                     # Big-endian
                     acc_value >> (acc_bits+(8*(out_width-x-1)))
@@ -59,12 +59,12 @@ def compress_array(inp, out_len, bit_len, byte_pad=0):
     acc_value = 0;
 
     j = 0
-    for i in xrange(out_len):
+    for i in range(out_len):
         # When we have fewer than 8 bits left in the accumulator, read the next
         # input element.
         if acc_bits < 8:
             acc_value = ((acc_value << bit_len) & word_mask) | inp[j]
-            for x in xrange(byte_pad, in_width):
+            for x in range(byte_pad, in_width):
                 acc_value = acc_value | (
                     (
                         # Apply bit_len_mask across byte boundaries
@@ -135,7 +135,7 @@ def gbp_basic(digest, n, k):
     indices_per_hash_output = 512/n
 
     # 1) Generate first list
-    if DEBUG: print 'Generating first list'
+    if DEBUG: print('Generating first list')
     X = []
     tmp_hash = ''
     for i in range(0, 2**(collision_length+1)):
@@ -153,16 +153,16 @@ def gbp_basic(digest, n, k):
 
     # 3) Repeat step 2 until 2n/(k+1) bits remain
     for i in range(1, k):
-        if DEBUG: print 'Round %d:' % i
+        if DEBUG:print('Round %d:' % i)
 
         # 2a) Sort the list
-        if DEBUG: print '- Sorting list'
+        if DEBUG: print('- Sorting list')
         X.sort(key=itemgetter(0))
         if DEBUG and VERBOSE:
             for Xi in X[-32:]:
-                print '%s %s' % (print_hash(Xi[0]), Xi[1])
+                print('%s %s' % (print_hash(Xi[0]), Xi[1]))
 
-        if DEBUG: print '- Finding collisions'
+        if DEBUG: print('- Finding collisions')
         Xc = []
         while len(X) > 0:
             # 2b) Find next set of unordered pairs with collisions on first n/(k+1) bits
@@ -192,13 +192,13 @@ def gbp_basic(digest, n, k):
 
     # k+1) Find a collision on last 2n(k+1) bits
     if DEBUG:
-        print 'Final round:'
-        print '- Sorting list'
+        print('Final round:')
+        print('- Sorting list')
     X.sort(key=itemgetter(0))
     if DEBUG and VERBOSE:
         for Xi in X[-32:]:
-            print '%s %s' % (print_hash(Xi[0]), Xi[1])
-    if DEBUG: print '- Finding collisions'
+            print('%s %s' % (print_hash(Xi[0]), Xi[1]))
+    if DEBUG: print('- Finding collisions')
     solns = []
     while len(X) > 0:
         j = 1
@@ -213,9 +213,9 @@ def gbp_basic(digest, n, k):
                 res = xor(X[-1-l][0], X[-1-m][0])
                 if count_zeroes(res) == 8*hash_length and distinct_indices(X[-1-l][1], X[-1-m][1]):
                     if DEBUG and VERBOSE:
-                        print 'Found solution:'
-                        print '- %s %s' % (print_hash(X[-1-l][0]), X[-1-l][1])
-                        print '- %s %s' % (print_hash(X[-1-m][0]), X[-1-m][1])
+                        print('Found solution:')
+                        print('- %s %s' % (print_hash(X[-1-l][0]), X[-1-l][1]))
+                        print('- %s %s' % (print_hash(X[-1-m][0]), X[-1-m][1]))
                     if X[-1-l][1][0] < X[-1-m][1][0]:
                         solns.append(list(X[-1-l][1] + X[-1-m][1]))
                     else:
@@ -235,8 +235,8 @@ def gbp_validate(digest, minimal, n, k):
     solution_width = (1 << k)*(collision_length+1)//8
 
     if len(minimal) != solution_width:
-        print 'Invalid solution length: %d (expected %d)' % \
-            (len(minimal), solution_width)
+        print('Invalid solution length: %d (expected %d)' % \
+            (len(minimal), solution_width))
         return False
 
     X = []
@@ -256,23 +256,23 @@ def gbp_validate(digest, minimal, n, k):
         Xc = []
         for i in range(0, len(X), 2):
             if not has_collision(X[i][0], X[i+1][0], r, collision_length):
-                print 'Invalid solution: invalid collision length between StepRows'
+                print('Invalid solution: invalid collision length between StepRows')
                 return False
             if X[i+1][1][0] < X[i][1][0]:
-                print 'Invalid solution: Index tree incorrectly ordered'
+                print('Invalid solution: Index tree incorrectly ordered')
                 return False
             if not distinct_indices(X[i][1], X[i+1][1]):
-                print 'Invalid solution: duplicate indices'
+                print('Invalid solution: duplicate indices')
                 return False
             Xc.append((xor(X[i][0], X[i+1][0]), X[i][1] + X[i+1][1]))
         X = Xc
 
     if len(X) != 1:
-        print 'Invalid solution: incorrect length after end of rounds: %d' % len(X)
+        print('Invalid solution: incorrect length after end of rounds: %d' % len(X))
         return False
 
     if count_zeroes(X[0][0]) != 8*hash_length:
-        print 'Invalid solution: incorrect number of zeroes: %d' % count_zeroes(X[0][0])
+        print('Invalid solution: incorrect number of zeroes: %d' % count_zeroes(X[0][0]))
         return False
 
     return True
diff --git a/qa/rpc-tests/test_framework/mininode.py b/qa/rpc-tests/test_framework/mininode.py
index ee323c580..0bbbd9e77 100755
--- a/qa/rpc-tests/test_framework/mininode.py
+++ b/qa/rpc-tests/test_framework/mininode.py
@@ -24,7 +24,7 @@ import binascii
 import time
 import sys
 import random
-import cStringIO
+import io
 import hashlib
 from threading import RLock
 from threading import Thread
@@ -32,7 +32,7 @@ import logging
 import copy
 from pyblake2 import blake2b
 
-from .equihash import (
+from test_framework.equihash import (
     gbp_basic,
     gbp_validate,
     hash_nonce,
@@ -100,14 +100,14 @@ def ser_string(s):
         return chr(len(s)) + s
     elif len(s) < 0x10000:
         return chr(253) + struct.pack("<H", len(s)) + s
-    elif len(s) < 0x100000000L:
+    elif len(s) < 0x100000000:
         return chr(254) + struct.pack("<I", len(s)) + s
     return chr(255) + struct.pack("<Q", len(s)) + s
 
 
 def deser_uint256(f):
-    r = 0L
-    for i in xrange(8):
+    r = 0
+    for i in range(8):
         t = struct.unpack("<I", f.read(4))[0]
         r += t << (i * 32)
     return r
@@ -115,23 +115,23 @@ def deser_uint256(f):
 
 def ser_uint256(u):
     rs = ""
-    for i in xrange(8):
-        rs += struct.pack("<I", u & 0xFFFFFFFFL)
+    for i in range(8):
+        rs += struct.pack("<I", u & 0xFFFFFFFF)
         u >>= 32
     return rs
 
 
 def uint256_from_str(s):
-    r = 0L
+    r = 0
     t = struct.unpack("<IIIIIIII", s[:32])
-    for i in xrange(8):
+    for i in range(8):
         r += t[i] << (i * 32)
     return r
 
 
 def uint256_from_compact(c):
     nbytes = (c >> 24) & 0xFF
-    v = (c & 0xFFFFFFL) << (8 * (nbytes - 3))
+    v = (c & 0xFFFFFF) << (8 * (nbytes - 3))
     return v
 
 
@@ -144,7 +144,7 @@ def deser_vector(f, c):
     elif nit == 255:
         nit = struct.unpack("<Q", f.read(8))[0]
     r = []
-    for i in xrange(nit):
+    for i in range(nit):
         t = c()
         t.deserialize(f)
         r.append(t)
@@ -157,7 +157,7 @@ def ser_vector(l):
         r = chr(len(l))
     elif len(l) < 0x10000:
         r = chr(253) + struct.pack("<H", len(l))
-    elif len(l) < 0x100000000L:
+    elif len(l) < 0x100000000:
         r = chr(254) + struct.pack("<I", len(l))
     else:
         r = chr(255) + struct.pack("<Q", len(l))
@@ -175,7 +175,7 @@ def deser_uint256_vector(f):
     elif nit == 255:
         nit = struct.unpack("<Q", f.read(8))[0]
     r = []
-    for i in xrange(nit):
+    for i in range(nit):
         t = deser_uint256(f)
         r.append(t)
     return r
@@ -187,7 +187,7 @@ def ser_uint256_vector(l):
         r = chr(len(l))
     elif len(l) < 0x10000:
         r = chr(253) + struct.pack("<H", len(l))
-    elif len(l) < 0x100000000L:
+    elif len(l) < 0x100000000:
         r = chr(254) + struct.pack("<I", len(l))
     else:
         r = chr(255) + struct.pack("<Q", len(l))
@@ -205,7 +205,7 @@ def deser_string_vector(f):
     elif nit == 255:
         nit = struct.unpack("<Q", f.read(8))[0]
     r = []
-    for i in xrange(nit):
+    for i in range(nit):
         t = deser_string(f)
         r.append(t)
     return r
@@ -217,7 +217,7 @@ def ser_string_vector(l):
         r = chr(len(l))
     elif len(l) < 0x10000:
         r = chr(253) + struct.pack("<H", len(l))
-    elif len(l) < 0x100000000L:
+    elif len(l) < 0x100000000:
         r = chr(254) + struct.pack("<I", len(l))
     else:
         r = chr(255) + struct.pack("<Q", len(l))
@@ -235,7 +235,7 @@ def deser_int_vector(f):
     elif nit == 255:
         nit = struct.unpack("<Q", f.read(8))[0]
     r = []
-    for i in xrange(nit):
+    for i in range(nit):
         t = struct.unpack("<i", f.read(4))[0]
         r.append(t)
     return r
@@ -247,7 +247,7 @@ def ser_int_vector(l):
         r = chr(len(l))
     elif len(l) < 0x10000:
         r = chr(253) + struct.pack("<H", len(l))
-    elif len(l) < 0x100000000L:
+    elif len(l) < 0x100000000:
         r = chr(254) + struct.pack("<I", len(l))
     else:
         r = chr(255) + struct.pack("<Q", len(l))
@@ -265,7 +265,7 @@ def deser_char_vector(f):
     elif nit == 255:
         nit = struct.unpack("<Q", f.read(8))[0]
     r = []
-    for i in xrange(nit):
+    for i in range(nit):
         t = struct.unpack("<B", f.read(1))[0]
         r.append(t)
     return r
@@ -277,7 +277,7 @@ def ser_char_vector(l):
         r = chr(len(l))
     elif len(l) < 0x10000:
         r = chr(253) + struct.pack("<H", len(l))
-    elif len(l) < 0x100000000L:
+    elif len(l) < 0x100000000:
         r = chr(254) + struct.pack("<I", len(l))
     else:
         r = chr(255) + struct.pack("<Q", len(l))
@@ -288,7 +288,7 @@ def ser_char_vector(l):
 
 # Objects that map to bitcoind objects, which can be serialized/deserialized
 
-class CAddress(object):
+class CAddress():
     def __init__(self):
         self.nServices = 1
         self.pchReserved = "\x00" * 10 + "\xff" * 2
@@ -314,13 +314,13 @@ class CAddress(object):
                                                          self.ip, self.port)
 
 
-class CInv(object):
+class CInv():
     typemap = {
         0: "Error",
         1: "TX",
         2: "Block"}
 
-    def __init__(self, t=0, h=0L):
+    def __init__(self, t=0, h=0):
         self.type = t
         self.hash = h
 
@@ -339,7 +339,7 @@ class CInv(object):
             % (self.typemap[self.type], self.hash)
 
 
-class CBlockLocator(object):
+class CBlockLocator():
     def __init__(self):
         self.nVersion = SPROUT_PROTO_VERSION
         self.vHave = []
@@ -359,7 +359,7 @@ class CBlockLocator(object):
             % (self.nVersion, self.vHave)
 
 
-class SpendDescription(object):
+class SpendDescription():
     def __init__(self):
         self.cv = None
         self.anchor = None
@@ -391,7 +391,7 @@ class SpendDescription(object):
             % (self.cv, self.anchor, self.nullifier, self.rk, self.zkproof, self.spendauthsig)
 
 
-class OutputDescription(object):
+class OutputDescription():
     def __init__(self):
         self.cv = None
         self.cmu = None
@@ -426,7 +426,7 @@ class OutputDescription(object):
 G1_PREFIX_MASK = 0x02
 G2_PREFIX_MASK = 0x0a
 
-class ZCProof(object):
+class ZCProof():
     def __init__(self):
         self.g_A = None
         self.g_A_prime = None
@@ -507,7 +507,7 @@ ZC_NOTECIPHERTEXT_SIZE = (
   NOTEENCRYPTION_AUTH_BYTES
 )
 
-class JSDescription(object):
+class JSDescription():
     def __init__(self):
         self.vpub_old = 0
         self.vpub_new = 0
@@ -571,7 +571,7 @@ class JSDescription(object):
                self.onetimePubKey, self.randomSeed, self.proof)
 
 
-class COutPoint(object):
+class COutPoint():
     def __init__(self, hash=0, n=0):
         self.hash = hash
         self.n = n
@@ -590,7 +590,7 @@ class COutPoint(object):
         return "COutPoint(hash=%064x n=%i)" % (self.hash, self.n)
 
 
-class CTxIn(object):
+class CTxIn():
     def __init__(self, outpoint=None, scriptSig="", nSequence=0):
         if outpoint is None:
             self.prevout = COutPoint()
@@ -618,7 +618,7 @@ class CTxIn(object):
                self.nSequence)
 
 
-class CTxOut(object):
+class CTxOut():
     def __init__(self, nValue=0, scriptPubKey=""):
         self.nValue = nValue
         self.scriptPubKey = scriptPubKey
@@ -639,7 +639,7 @@ class CTxOut(object):
                binascii.hexlify(self.scriptPubKey))
 
 
-class CTransaction(object):
+class CTransaction():
     def __init__(self, tx=None):
         if tx is None:
             self.fOverwintered = True
@@ -756,7 +756,7 @@ class CTransaction(object):
     def is_valid(self):
         self.calc_sha256()
         for tout in self.vout:
-            if tout.nValue < 0 or tout.nValue > 21000000L * 100000000L:
+            if tout.nValue < 0 or tout.nValue > 2100000 * 100000000:
                 return False
         return True
 
@@ -778,7 +778,7 @@ class CTransaction(object):
         return r
 
 
-class CBlockHeader(object):
+class CBlockHeader():
     def __init__(self, header=None):
         if header is None:
             self.set_null()
@@ -878,7 +878,7 @@ class CBlock(CBlockHeader):
             hashes.append(ser_uint256(tx.sha256))
         while len(hashes) > 1:
             newhashes = []
-            for i in xrange(0, len(hashes), 2):
+            for i in range(0, len(hashes), 2):
                 i2 = min(i+1, len(hashes)-1)
                 newhashes.append(hash256(hashes[i] + hashes[i2]))
             hashes = newhashes
@@ -929,7 +929,7 @@ class CBlock(CBlockHeader):
                self.nNonce, self.nSolution, self.vtx)
 
 
-class CUnsignedAlert(object):
+class CUnsignedAlert():
     def __init__(self):
         self.nVersion = 1
         self.nRelayUntil = 0
@@ -984,7 +984,7 @@ class CUnsignedAlert(object):
                self.strComment, self.strStatusBar, self.strReserved)
 
 
-class CAlert(object):
+class CAlert():
     def __init__(self):
         self.vchMsg = ""
         self.vchSig = ""
@@ -1005,7 +1005,7 @@ class CAlert(object):
 
 
 # Objects that correspond to messages on the wire
-class msg_version(object):
+class msg_version():
     command = "version"
 
     def __init__(self, protocol_version=SPROUT_PROTO_VERSION):
@@ -1060,7 +1060,7 @@ class msg_version(object):
                self.strSubVer, self.nStartingHeight)
 
 
-class msg_verack(object):
+class msg_verack():
     command = "verack"
 
     def __init__(self):
@@ -1076,7 +1076,7 @@ class msg_verack(object):
         return "msg_verack()"
 
 
-class msg_addr(object):
+class msg_addr():
     command = "addr"
 
     def __init__(self):
@@ -1092,7 +1092,7 @@ class msg_addr(object):
         return "msg_addr(addrs=%r)" % (self.addrs,)
 
 
-class msg_alert(object):
+class msg_alert():
     command = "alert"
 
     def __init__(self):
@@ -1111,7 +1111,7 @@ class msg_alert(object):
         return "msg_alert(alert=%r)" % (self.alert,)
 
 
-class msg_inv(object):
+class msg_inv():
     command = "inv"
 
     def __init__(self, inv=None):
@@ -1130,7 +1130,7 @@ class msg_inv(object):
         return "msg_inv(inv=%r)" % (self.inv,)
 
 
-class msg_getdata(object):
+class msg_getdata():
     command = "getdata"
 
     def __init__(self):
@@ -1146,7 +1146,7 @@ class msg_getdata(object):
         return "msg_getdata(inv=%r)" % (self.inv,)
 
 
-class msg_notfound(object):
+class msg_notfound():
     command = "notfound"
 
     def __init__(self):
@@ -1162,12 +1162,12 @@ class msg_notfound(object):
         return "msg_notfound(inv=%r)" % (self.inv,)
 
 
-class msg_getblocks(object):
+class msg_getblocks():
     command = "getblocks"
 
     def __init__(self):
         self.locator = CBlockLocator()
-        self.hashstop = 0L
+        self.hashstop = 0
 
     def deserialize(self, f):
         self.locator = CBlockLocator()
@@ -1185,7 +1185,7 @@ class msg_getblocks(object):
             % (self.locator, self.hashstop)
 
 
-class msg_tx(object):
+class msg_tx():
     command = "tx"
 
     def __init__(self, tx=CTransaction()):
@@ -1201,7 +1201,7 @@ class msg_tx(object):
         return "msg_tx(tx=%r)" % (self.tx,)
 
 
-class msg_block(object):
+class msg_block():
     command = "block"
 
     def __init__(self, block=None):
@@ -1220,7 +1220,7 @@ class msg_block(object):
         return "msg_block(block=%r)" % (self.block,)
 
 
-class msg_getaddr(object):
+class msg_getaddr():
     command = "getaddr"
 
     def __init__(self):
@@ -1236,7 +1236,7 @@ class msg_getaddr(object):
         return "msg_getaddr()"
 
 
-class msg_ping_prebip31(object):
+class msg_ping_prebip31():
     command = "ping"
 
     def __init__(self):
@@ -1252,10 +1252,10 @@ class msg_ping_prebip31(object):
         return "msg_ping() (pre-bip31)"
 
 
-class msg_ping(object):
+class msg_ping():
     command = "ping"
 
-    def __init__(self, nonce=0L):
+    def __init__(self, nonce=0):
         self.nonce = nonce
 
     def deserialize(self, f):
@@ -1270,10 +1270,10 @@ class msg_ping(object):
         return "msg_ping(nonce=%08x)" % self.nonce
 
 
-class msg_pong(object):
+class msg_pong():
     command = "pong"
 
-    def __init__(self, nonce=0L):
+    def __init__(self, nonce=0):
         self.nonce = nonce
 
     def deserialize(self, f):
@@ -1288,7 +1288,7 @@ class msg_pong(object):
         return "msg_pong(nonce=%08x)" % self.nonce
 
 
-class msg_mempool(object):
+class msg_mempool():
     command = "mempool"
 
     def __init__(self):
@@ -1308,12 +1308,12 @@ class msg_mempool(object):
 # number of entries
 # vector of hashes
 # hash_stop (hash of last desired block header, 0 to get as many as possible)
-class msg_getheaders(object):
+class msg_getheaders():
     command = "getheaders"
 
     def __init__(self):
         self.locator = CBlockLocator()
-        self.hashstop = 0L
+        self.hashstop = 0
 
     def deserialize(self, f):
         self.locator = CBlockLocator()
@@ -1333,7 +1333,7 @@ class msg_getheaders(object):
 
 # headers message has
 # <count> <vector of block headers>
-class msg_headers(object):
+class msg_headers():
     command = "headers"
 
     def __init__(self):
@@ -1353,14 +1353,14 @@ class msg_headers(object):
         return "msg_headers(headers=%r)" % (self.headers,)
 
 
-class msg_reject(object):
+class msg_reject():
     command = "reject"
 
     def __init__(self):
         self.message = ""
         self.code = ""
         self.reason = ""
-        self.data = 0L
+        self.data = 0
 
     def deserialize(self, f):
         self.message = deser_string(f)
@@ -1382,7 +1382,7 @@ class msg_reject(object):
             % (self.message, self.code, self.reason, self.data)
 
 
-class msg_filteradd(object):
+class msg_filteradd():
     command = "filteradd"
 
     def __init__(self):
@@ -1398,7 +1398,7 @@ class msg_filteradd(object):
         return "msg_filteradd(data=%r)" % (self.data,)
 
 
-class msg_filterclear(object):
+class msg_filterclear():
     command = "filterclear"
 
     def __init__(self):
@@ -1416,7 +1416,7 @@ class msg_filterclear(object):
 
 # This is what a callback should look like for NodeConn
 # Reimplement the on_* functions to provide handling for events
-class NodeConnCB(object):
+class NodeConnCB():
     def __init__(self):
         self.verack_received = False
 
@@ -1448,8 +1448,8 @@ class NodeConnCB(object):
             try:
                 self.cbmap[message.command](conn, message)
             except:
-                print "ERROR delivering %r (%s)" % (message,
-                                                    sys.exc_info()[0])
+                print("ERROR delivering %r (%s)" % (message,
+                                                    sys.exc_info()[0]))
 
     def on_version(self, conn, message):
         if message.nVersion >= 209:
@@ -1540,8 +1540,8 @@ class NodeConn(asyncore.dispatcher):
         vt.addrFrom.ip = "0.0.0.0"
         vt.addrFrom.port = 0
         self.send_message(vt, True)
-        print 'MiniNode: Connecting to Bitcoin Node IP # ' + dstaddr + ':' \
-            + str(dstport) + ' using version ' + str(protocol_version)
+        print('MiniNode: Connecting to Bitcoin Node IP # ' + dstaddr + ':' \
+            + str(dstport) + ' using version ' + str(protocol_version))
 
         try:
             self.connect((dstaddr, dstport))
@@ -1625,7 +1625,7 @@ class NodeConn(asyncore.dispatcher):
                     raise ValueError("got bad checksum %r" % (self.recvbuf,))
                 self.recvbuf = self.recvbuf[4+12+4+4+msglen:]
             if command in self.messagemap:
-                f = cStringIO.StringIO(msg)
+                f = io.StringIO(msg)
                 t = self.messagemap[command]()
                 t.deserialize(f)
                 self.got_message(t)
diff --git a/qa/rpc-tests/test_framework/netutil.py b/qa/rpc-tests/test_framework/netutil.py
index ba1e8b0d6..38e0dab26 100644
--- a/qa/rpc-tests/test_framework/netutil.py
+++ b/qa/rpc-tests/test_framework/netutil.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2
+#!/usr/bin/env python3
 # Copyright (c) 2014 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or https://www.opensource.org/licenses/mit-license.php .
diff --git a/qa/rpc-tests/test_framework/script.py b/qa/rpc-tests/test_framework/script.py
index e7aa12e93..4440ae940 100644
--- a/qa/rpc-tests/test_framework/script.py
+++ b/qa/rpc-tests/test_framework/script.py
@@ -1,4 +1,3 @@
-#
 # script.py
 #
 # This file is modified from python-bitcoinlib.
@@ -12,8 +11,6 @@
 Functionality to build scripts, as well as SignatureHash().
 """
 
-from __future__ import absolute_import, division, print_function, unicode_literals
-
 from test_framework.mininode import CTransaction, CTxOut, hash256
 
 import sys
diff --git a/qa/rpc-tests/test_framework/socks5.py b/qa/rpc-tests/test_framework/socks5.py
index 813654e52..1e2dda807 100644
--- a/qa/rpc-tests/test_framework/socks5.py
+++ b/qa/rpc-tests/test_framework/socks5.py
@@ -4,8 +4,8 @@
 '''
 Dummy Socks5 server for testing.
 '''
-from __future__ import print_function, division, unicode_literals
-import socket, threading, Queue
+
+import socket, threading
 import traceback, sys
 
 ### Protocol constants
@@ -117,7 +117,7 @@ class Socks5Connection(object):
             self.serv.queue.put(cmdin)
             print('Proxy: ', cmdin)
             # Fall through to disconnect
-        except Exception,e:
+        except Exception as e:
             traceback.print_exc(file=sys.stderr)
             self.serv.queue.put(e)
         finally:
@@ -132,7 +132,7 @@ class Socks5Server(object):
         self.s.listen(5)
         self.running = False
         self.thread = None
-        self.queue = Queue.Queue() # report connections and exceptions to client
+        self.queue = queue.Queue() # report connections and exceptions to client
 
     def run(self):
         while self.running:
diff --git a/qa/rpc-tests/test_framework/test_framework.py b/qa/rpc-tests/test_framework/test_framework.py
index 067b2dce3..30fe52691 100755
--- a/qa/rpc-tests/test_framework/test_framework.py
+++ b/qa/rpc-tests/test_framework/test_framework.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2
+#!/usr/bin/env python3
 # Copyright (c) 2014 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or https://www.opensource.org/licenses/mit-license.php .
@@ -13,8 +13,8 @@ import shutil
 import tempfile
 import traceback
 
-from authproxy import JSONRPCException
-from util import assert_equal, check_json_precision, \
+from .authproxy import JSONRPCException
+from .util import assert_equal, check_json_precision, \
     initialize_chain, initialize_chain_clean, \
     start_nodes, connect_nodes_bi, stop_nodes, \
     sync_blocks, sync_mempools, wait_bitcoinds
@@ -172,7 +172,7 @@ class ComparisonTestFramework(BitcoinTestFramework):
                           help="bitcoind binary to use for reference nodes (if any)")
 
     def setup_chain(self):
-        print "Initializing test directory "+self.options.tmpdir
+        print("Initializing test directory "+self.options.tmpdir)
         initialize_chain_clean(self.options.tmpdir, self.num_nodes)
 
     def setup_network(self):
diff --git a/qa/rpc-tests/test_framework/util.py b/qa/rpc-tests/test_framework/util.py
index a2095cd65..bf1da0904 100644
--- a/qa/rpc-tests/test_framework/util.py
+++ b/qa/rpc-tests/test_framework/util.py
@@ -21,7 +21,7 @@ import subprocess
 import time
 import re
 
-from authproxy import AuthServiceProxy
+from .authproxy import AuthServiceProxy
 
 PRE_BLOSSOM_BLOCK_TARGET_SPACING = 150
 POST_BLOSSOM_BLOCK_TARGET_SPACING = 75
@@ -147,11 +147,11 @@ def initialize_chain(test_dir):
                 args.append("-connect=127.0.0.1:"+str(p2p_port(0)))
             bitcoind_processes[i] = subprocess.Popen(args)
             if os.getenv("PYTHON_DEBUG", ""):
-                print "initialize_chain: bitcoind started, calling bitcoin-cli -rpcwait getblockcount"
+                print("initialize_chain: bitcoind started, calling bitcoin-cli -rpcwait getblockcount")
             subprocess.check_call([ os.getenv("BITCOINCLI", "bitcoin-cli"), "-datadir="+datadir,
                                     "-rpcwait", "getblockcount"], stdout=devnull)
             if os.getenv("PYTHON_DEBUG", ""):
-                print "initialize_chain: bitcoin-cli -rpcwait getblockcount completed"
+                print("initialize_chain: bitcoin-cli -rpcwait getblockcount completed")
         devnull.close()
         rpcs = []
         for i in range(4):
@@ -239,12 +239,12 @@ def start_node(i, dirname, extra_args=None, rpchost=None, timewait=None, binary=
     bitcoind_processes[i] = subprocess.Popen(args)
     devnull = open("/dev/null", "w+")
     if os.getenv("PYTHON_DEBUG", ""):
-        print "start_node: bitcoind started, calling bitcoin-cli -rpcwait getblockcount"
+        print("start_node: bitcoind started, calling bitcoin-cli -rpcwait getblockcount")
     subprocess.check_call([ os.getenv("BITCOINCLI", "bitcoin-cli"), "-datadir="+datadir] +
                           _rpchost_to_args(rpchost)  +
                           ["-rpcwait", "getblockcount"], stdout=devnull)
     if os.getenv("PYTHON_DEBUG", ""):
-        print "start_node: calling bitcoin-cli -rpcwait getblockcount returned"
+        print("start_node: calling bitcoin-cli -rpcwait getblockcount returned")
     devnull.close()
     url = "http://rt:rt@%s:%d" % (rpchost or '127.0.0.1', rpc_port(i))
     if timewait is not None:
@@ -442,7 +442,7 @@ def fail(message=""):
 def wait_and_assert_operationid_status_result(node, myopid, in_status='success', in_errormsg=None, timeout=300):
     print('waiting for async operation {}'.format(myopid))
     result = None
-    for _ in xrange(1, timeout):
+    for _ in range(1, timeout):
         results = node.z_getoperationresult([myopid])
         if len(results) > 0:
             result = results[0]