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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 create_access_token_data(self, grant_type):
 """ Create data needed by an access token. :param grant_type: :type grant_type: str :return: A ``dict`` containing he ``access_token`` and the ``token_type``. If the value of ``TokenGenerator.expires_in`` is larger than 0, a ``refresh_token`` will be generated too. :rtype: dict """

        result = {"access_token": self.generate(), "token_type": "Bearer"}

        if self.expires_in.get(grant_type, 0) > 0:
            result["refresh_token"] = self.generate()

            result["expires_in"] = self.expires_in[grant_type]

        return result