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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_signing_key(self, algorithm, service_context):
 """ Pick signing key based on signing algorithm to be used :param algorithm: Signing algorithm :param service_context: A :py:class:`oidcservice.service_context.ServiceContext` instance :return: A key """

        return service_context.keyjar.get_signing_key(
            alg2keytype(algorithm), alg=algorithm)