def METHOD_NAME(prm, is_input):
    """ Encode process description ComplexData (parameter definition) element.
    """
    return NIL("ComplexData" if is_input else "ComplexOutput",
        NIL("Default", _encode_format(prm.default_format)),
        NIL("Supported", *[_encode_format(f) for f in itervalues(prm.formats)])
    )