_inputstream.py 文件源码

def openStream(self, source):
        """Produces a file object from source.

        source can be either a file object, local filename or a string.

        """
        # Already a file object
        if hasattr(source, 'read'):
            stream = source
        else:
            stream = BytesIO(source)

        try:
            stream.seek(stream.tell())
        except:  # pylint:disable=bare-except
            stream = BufferedStream(stream)

        return stream