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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, key_type="", owner="", kid=None, **kwargs):
 """ Shortcut to use for signing keys only. :param key_type: Type of key (rsa, ec, oct, ..) :param owner: Who is the owner of the keys, "" == me (default) :param kid: A Key Identifier :param kwargs: Extra key word arguments :return: A possibly empty list of keys """

        return self.get("sig", key_type, owner, kid, **kwargs)