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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 is_scn(self):
 """Page contains Leica SCN XML in ImageDescription tag."""

        if self.index > 1 or not self.description:
            return False
        d = self.description
        return d[:14] == '<?xml version=' and d[-6:] == '</scn>'