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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, fn=None):
 """copy the zip file from its filename to the given filename."""

        fn = fn or self.fn
        if not os.path.exists(os.path.dirname(fn)):
            os.makedirs(os.path.dirname(fn))
        f = open(self.fn, 'rb')
        b = f.read()
        f.close()
        f = open(fn, 'wb')
        f.write(b)
        f.close()