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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 register(self, identified_with, identifier, user):
 """Register new key for given client identifier. This is only a helper method that allows to register new user objects for client identities (keys, tokens, addresses etc.). Args: identified_with (object):
 authentication middleware used to identify the user. identifier (str):
 user identifier. user (str):
 user object to be stored in the backend. """

        self.kv_store.set(
            self._get_storage_key(identified_with, identifier),
            self.serialization.dumps(user).encode(),
        )