Fix warnings

tests/integration/__init__.py

@@ -976,9 +976,9 @@ def __new__(cls, **kwargs):
 # introduced by CASSANDRA-15234
 class Cassandra41CCMCluster(CCMCluster):
     __test__ = False
-    IN_MS_REGEX = re.compile('^(\w+)_in_ms$')
-    IN_KB_REGEX = re.compile('^(\w+)_in_kb$')
-    ENABLE_REGEX = re.compile('^enable_(\w+)$')
+    IN_MS_REGEX = re.compile(r'^(\w+)_in_ms$')
+    IN_KB_REGEX = re.compile(r'^(\w+)_in_kb$')
+    ENABLE_REGEX = re.compile(r'^enable_(\w+)$')
 
     def _get_config_key(self, k, v):
         if "." in k:

tests/unit/io/utils.py

@@ -120,7 +120,7 @@ def submit_and_wait_for_completion(unit_test, create_timer, start, end, incremen
         pending_callbacks.append(callback)
 
     # wait for all the callbacks associated with the timers to be invoked
-    while len(pending_callbacks) is not 0:
+    while len(pending_callbacks) != 0:
         for callback in pending_callbacks:
             if callback.was_invoked():
                 pending_callbacks.remove(callback)

tests/unit/test_exception.py

@@ -29,7 +29,7 @@ def extract_consistency(self, msg):
         :param msg: message with consistency value
         :return: String representing consistency value
         """
-        match = re.search("'consistency':\s+'([\w\s]+)'", msg)
+        match = re.search(r"'consistency':\s+'([\w\s]+)'", msg)
         return match and match.group(1)
 
     def test_timeout_consistency(self):