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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_joined_members(self, force_resync=False) -> List[User]: """ Return a list of members of this room. """

        if force_resync:
            response = self.client.api.get_room_members(self.room_id)
            for event in response['chunk']:
                if event['content']['membership'] == 'join':
                    user_id = event["state_key"]
                    if user_id not in self._members:
                        self._mkmembers(
                            User(
                                self.client.api,
                                user_id,
                                event['content'].get('displayname'),
                            ),
                        )
        return list(self._members.values())