@staticmethod
def p_kp_data_parameter_optional_list(p):
    """kp_data_parameter_optional_list : kp_data_parameter_optional
                                           | kp_data_parameter_optional kp_data_parameter_optional_list"""
    try:
        p[0] = [p[1]] + p[2]
    except IndexError:
        p[0] = [p[1]]
    p[0] = p[1]
