def __init__(self, obj, attrname, readable_name=None):
        """
        Args:
            obj: the object
            attrname (str): the attribute
            readable_name(str): The name to display and set with. Defaults to be ``attrname``.
        """
        self.obj = obj
        self.attrname = attrname
        if readable_name is None:
            self._readable_name = attrname
        else:
            self._readable_name = readable_name

        Args:
            obj: the object
            attrname (str): the attribute
            readable_name(str): The name to display and set with. Defaults to be ``attrname``.
        
tensorpack/callbacks/param.py