add an example here to demonstrate async functionality

Author: Lingling Peng

synapseclient/models/team.py

@@ -448,6 +448,35 @@ async def get_user_membership_status_async(
 
         Returns:
             TeamMembershipStatus object
+
+        Example: Check if a user is a member of a team
+        This example shows how to check a user's membership status in a team.
+
+        ```python
+        import asyncio
+        from synapseclient import Synapse
+        from synapseclient.models import Team
+
+        syn = Synapse()
+        syn.login()
+
+        async def check_membership():
+            # Get a team by ID
+            team = await Team.from_id_async(123456)
+
+            # Check membership status for a specific user
+            user_id = "3350396"  # Replace with actual user ID
+            status = await team.get_user_membership_status_async(user_id)
+
+            print(f"User ID: {status.user_id}")
+            print(f"Is member: {status.is_member}")
+            print(f"Can join: {status.can_join}")
+            print(f"Has open invitation: {status.has_open_invitation}")
+            print(f"Has open request: {status.has_open_request}")
+            print(f"Membership approval required: {status.membership_approval_required}")
+
+        asyncio.run(check_membership())
+        ```
         """
         from synapseclient import Synapse