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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 refresh(self, client_name, refresh_token, **params):
 """Get refresh token. :param client_name: A name one of configured clients :param redirect_uri: An URI for authorization redirect :returns: a coroutine """

        client = self.client(client_name, logger=self.app.logger)
        return client.get_access_token(refresh_token, grant_type='refresh_token', **params)