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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 copy(self):
 """ Make deep copy of this key jar. :return: A :py:class:`oidcmsg.key_jar.KeyJar` instance """

        kj = KeyJar()
        for issuer in self.owners():
            kj[issuer] = [kb.copy() for kb in self[issuer]]

        kj.verify_ssl = self.verify_ssl
        return kj