Add anext helper

Author: NoahStapp

test/asynchronous/unified_format.py

@@ -74,6 +74,7 @@
 from pymongo.asynchronous.command_cursor import AsyncCommandCursor
 from pymongo.asynchronous.database import AsyncDatabase
 from pymongo.asynchronous.encryption import AsyncClientEncryption
+from pymongo.asynchronous.helpers import anext
 from pymongo.encryption_options import _HAVE_PYMONGOCRYPT
 from pymongo.errors import (
     BulkWriteError,

test/unified_format.py

@@ -97,6 +97,7 @@
 from pymongo.synchronous.command_cursor import CommandCursor
 from pymongo.synchronous.database import Database
 from pymongo.synchronous.encryption import ClientEncryption
+from pymongo.synchronous.helpers import next
 from pymongo.topology_description import TopologyDescription
 from pymongo.typings import _Address
 from pymongo.write_concern import WriteConcern