def set_client_cert(self, cert):
        """*Sets the client cert for the requests.*

        The cert is either a path to a .pem file, or a JSON array, or a list
        having the cert path and the key path.

        Values ``null`` and ``${None}`` can be used for clearing the cert.

        *Examples*

        | `Set Client Cert` | ${CURDIR}/client.pem |
        | `Set Client Cert` | ["${CURDIR}/client.cert", "${CURDIR}/client.key"] |
        | `Set Client Cert` | ${paths_list} |
        """
        self.request["cert"] = self._input_client_cert(cert)
        return self.request["cert"]