Merge pull request #3894 from matrix-org/hs/phone_home_py_version

Add python_version phone home stat

changelog.d/3894.feature

@@ -0,0 +1 @@
+Report "python_version" in the phone home stats

synapse/app/homeserver.py

@@ -457,6 +457,10 @@ def run(hs):
         stats["homeserver"] = hs.config.server_name
         stats["timestamp"] = now
         stats["uptime_seconds"] = uptime
+        version = sys.version_info
+        stats["python_version"] = "{}.{}.{}".format(
+            version.major, version.minor, version.micro
+        )
         stats["total_users"] = yield hs.get_datastore().count_all_users()
 
         total_nonbridged_users = yield hs.get_datastore().count_nonbridged_users()