switched all python2.7 to python3.x

ci/dependabot-pr.sh

@@ -23,7 +23,7 @@ echo --- "(FAILING) Backpropagating dependabot-triggered Cargo.lock updates"
 name="dependabot-buildkite"
 api_base="https://api.github.com/repos/solana-labs/solana/pulls"
 pr_num=$(echo "$BUILDKITE_BRANCH" | grep -Eo '[0-9]+')
-branch=$(curl -s "$api_base/$pr_num" | python -c 'import json,sys;print json.load(sys.stdin)["head"]["ref"]')
+branch=$(curl -s "$api_base/$pr_num" | python3 -c 'import json,sys;print json.load(sys.stdin)["head"]["ref"]')
 
 git add :**/Cargo.lock
 EMAIL="dependabot-buildkite@noreply.solana.com" \

scripts/perf-plot.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 import matplotlib
 matplotlib.use('Agg')

system-test/automation_utils.sh

@@ -163,7 +163,7 @@ function collect_performance_statistics {
   curl -G "${INFLUX_HOST}/query?u=ro&p=topsecret" \
     --data-urlencode "db=${TESTNET_TAG}" \
     --data-urlencode "q=$q_mean_tps;$q_max_tps;$q_mean_confirmation;$q_max_confirmation;$q_99th_confirmation;$q_max_tower_distance_observed;$q_last_tower_distance_observed" |
-    python "${REPO_ROOT}"/system-test/testnet-automation-json-parser.py >>"$RESULT_FILE"
+    python3 "${REPO_ROOT}"/system-test/testnet-automation-json-parser.py >>"$RESULT_FILE"
 
   declare q_dropped_vote_hash_count='
     SELECT sum("count") as "sum_dropped_vote_hash"
@@ -175,7 +175,7 @@ function collect_performance_statistics {
   curl -G "${INFLUX_HOST}/query?u=ro&p=topsecret" \
     --data-urlencode "db=${TESTNET_TAG}" \
     --data-urlencode "q=$q_dropped_vote_hash_count" |
-    python "${REPO_ROOT}"/system-test/testnet-automation-json-parser-missing.py)
+    python3 "${REPO_ROOT}"/system-test/testnet-automation-json-parser-missing.py)
 }
 
 function upload_results_to_slack() {