APP_ERROR = (-1, '服务器错误，请联系管理员进行处理。')
PARAMS_MISMATCH = (-2, '参数错误。')
API_NOT_FOUND = (-3, '无法找到对应API。')

MODEL_INVALID = (-11, '查询错误，模型名称无效。')
FIELD_INVALID = (-12, '查询错误，字段名称无效。')
OPERATOR_INVALID = (-13, '查询错误，操作符无效。')
