def write(self, file):
        """Write the image to the open file object.

        See `.save()` if you have a filename.

        In general, you can only call this method once;
        after it has been called the first time the PNG image is written,
        the source data will have been streamed, and
        cannot be streamed again.
        """

        w = Writer(**self.info)
        w.write(file, self.rows)
Write the image to the open file object.

        See `.save()` if you have a filename.

        In general, you can only call this method once;
        after it has been called the first time the PNG image is written,
        the source data will have been streamed, and
        cannot be streamed again.