def METHOD_NAME(self, service):
    """Test deserializing backend configuration."""
    instance = self.dependencies.instance if service.channel == "ibm_quantum" else None
    backends = service.backends(operational=True, open_pulse=True, instance=instance)
    if not backends:
        self.skipTest("Need pulse backends.")
    # Known keys that look like a serialized complex number.
    good_keys = ("cmd_def.qubits", "cmd_def.sequence.ch")
    for backend in backends:
        with self.subTest(backend=backend):
            self._verify_data(backend.defaults().to_dict(), good_keys)