Add docs.

Author: shibd

pulsar/__init__.py

@@ -780,6 +780,14 @@ def my_listener(consumer, message):
           Set the batch collection policy for batch receiving.
         key_shared_policy: class ConsumerKeySharedPolicy
             Set the key shared policy for use when the ConsumerType is KeyShared.
+        regex_subscription_mode: RegexSubscriptionMode, optional
+            Set the regex subscription mode for use when the topic is a regex pattern.
+
+            Supported modes:
+
+            * PersistentOnly: By default only subscribe to persistent topics.
+            * NonPersistentOnly: Only subscribe to non-persistent topics.
+            * AllTopics: Subscribe to both persistent and non-persistent topics.
         """
         _check_type(str, subscription_name, 'subscription_name')
         _check_type(ConsumerType, consumer_type, 'consumer_type')