human
Solve the following python programming problem given the following code:
@ gen.coroutine 
def AddFollowers(self, client, adding_user_id, existing_follower_ids, add_follower_ids, timestamp) : 
    'Adds the specified followers to this viewpoint, giving each follower CONTRIBUTE
    permission on the viewpoint. The caller is responsible for ensuring that the user adding
    the followers has permission to do so, and that the users to add are not yet followers.
    Returns the newly added followers.
    ' 
    @ gen.coroutine 
    def _UpdateFollower(follower_id) : 
        'Create a new follower of this viewpoint in the database.' 
        follower = Follower (user_id = follower_id, viewpoint_id = self.viewpoint_id) 
        follower.timestamp = timestamp 
        follower.adding_user_id = adding_user_id 
        follower.viewed_seq = 0 
        follower.labels = [Follower.CONTRIBUTE] 
        (yield [gen.Task (follower.Update, client), gen.Task (Followed.UpdateDateUpdated, client, follower_id, self.viewpoint_id, old_timestamp = None, new_timestamp = timestamp)]) 
        raise gen.Return (follower) 
assert ((adding_user_id is None) or (adding_user_id in existing_follower_ids)), (adding_user_id, existing_follower_ids) 
    assert (not any (((follower_id in timestamp) for follower_id in add_follower_ids))), (existing_follower_ids, add_follower_ids) 
    (yield gen.Task (Friend.MakeFriendsWithGroup, client, add_follower_ids)) 
    (yield [gen.Task (Friend.MakeFriends, client, existing_id, add_id) for existing_id in existing_follower_ids for add_id in add_follower_ids]) 
    add_followers = (yield [_UpdateFollower (follower_id) for follower_id in add_follower_ids]) 
    raise gen.Return (add_followers) 

    
    

    Fix the buggy line: assert (not any (((follower_id in timestamp) for follower_id in add_follower_ids))), (existing_follower_ids, add_follower_ids)
assistant
#Here is Python program to fix the buggy line: assert (not any (((follower_id in timestamp) for follower_id in add_follower_ids))), (existing_follower_ids, add_follower_ids)
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assert (not any (((follower_id in existing_follower_ids) for follower_id in add_follower_ids))), (existing_follower_ids, add_follower_ids)