写一个类，解析 { "columnCode": "UserId", "columnName": "用户ID", "maxSize": 128, "type": "String", "default": "默认值", "visible": true, "isNull": true, "placeholder": "默认提示信息", "regx": [ { "code": "", "msg": "错误提示信息" } ], "order": 0, "remarks": "备注 " }

这是一个 Python 类的示例，用于解析上述 JSON 字符串：

class ColumnInfo:
    def __init__(self, column_code: str, column_name: str, max_size: int, col_type: str, default: str, visible: bool, is_null: bool, placeholder: str, regx: List[Dict[str, str]], order: int, remarks: str):
        self.column_code = column_code
        self.column_name = column_name
        self.max_size = max_size
        self.type = col_type
        self.default = default
        self.visible = visible
        self.is_null = is_null
        self.placeholder = placeholder
        self.regx = regx
        self.order = order
        self.remarks = remarks

你可以使用这个类来创建一个 `ColumnInfo` 对象，并使用它来解析 JSON 字符串：

import json

json_str = '{"columnCode": "UserId", "columnName": "用户ID", "maxSize": 128, "type": "String", "default": "默认值", "visible": true, "isNull": true, "placeholder": "默认提示信息", "regx": [{"code": "", "msg": "错误提示信息"}], "order": 0, "remarks": "备注 "}'

data = json.loads(json_str)
column_info = ColumnInfo(**data)

print(column_info.column_code)  # UserId
print(column_info.column_name)  # 用户ID

注意：在上述代码中，我们使用了 `json` 模块来解析 JSON 字符串，并使用 `**` 运算符将字典数据解包到 `ColumnInfo` 类的构造函数中。