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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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)