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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 tell(self):
 """Returns the file offset. If this is a compressed file, then the offset in the compressed file is returned. """

        if isinstance(self.fileobj, gzip2.GzipFile):
            return self.fileobj.fileobj.tell()
        else:
            return self.fileobj.tell()