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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 _update_offset_file(self):
 """ Update the offset file with the current inode and offset. """

        if self.on_update:
            self.on_update()
        offset = self._filehandle().tell()
        inode = stat(self.filename).st_ino
        fh = open(self._offset_file, "w")
        fh.write("%s\n%s\n" % (inode, offset))
        fh.close()
        self._since_update = 0