动态替换模型的少量filed或method

model_wrapper.py

class ModelWrapper(object):
    """
    在原始模型之外进行一层外包封装。
    动态地替换原模型的属性。
    """
    def __init__(self, execute_model):
        self.execute_model = execute_model  # 实际运行的模型
        self.overwrite_model_attr()

    def overwrite_model_attr(self):
        """模型优先使用wrapper模型的方法"""
        attr_names = [attr_name for attr_name in dir(self)
                  if not attr_name.startswith("__")]
        # print(attr_names)
        for attr_name in attr_names:
            if hasattr(self.execute_model, attr_name):
                print(f"overwrite {attr_name} for original model {self.execute_model}")
                setattr(self.execute_model, attr_name, getattr(self, attr_name))

    def __getattr__(self, item):
        """若wrapper没有覆盖某属性，使用原模型的属性"""
        if hasattr(self.execute_model, item):
            return getattr(self.execute_model, item)
        else:
            raise AttributeError(f"{self} has not attribute {item} !")