tempfile.py 文件源码

def __getattr__(self, name):
        # Attribute lookups are delegated to the underlying file
        # and cached for non-numeric results
        # (i.e. methods are cached, closed and friends are not)
        file = self.__dict__['file']
        a = getattr(file, name)
        if hasattr(a, '__call__'):
            func = a
            @_functools.wraps(func)
            def func_wrapper(*args, **kwargs):
                return func(*args, **kwargs)
            # Avoid closing the file as long as the wrapper is alive,
            # see issue #18879.
            func_wrapper._closer = self._closer
            a = func_wrapper
        if not isinstance(a, int):
            setattr(self, name, a)
        return a

    # The underlying __enter__ method returns the wrong object
    # (self.file) so override it to return the wrapper