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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_with_password(self, username, password):
 """ Register for a new account on this HS. Args: username (str):
 Account username password (str):
 Account password Returns: str: Access Token Raises: MatrixRequestError """

        response = self.api.register(
                auth_body={"type": "m.login.dummy"},
                kind='user',
                username=username,
                password=password,
        )
        return self._post_registration(response)