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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 _fchown(self, real, fileno, uid, gid):
 """Run fake fchown code if fileno points to a sub-path of our tree. The ownership set with this fake fchown can be inspected by looking at the self.uid/self.gid dictionaries. """

        path = self._fake_path(self._path_from_fd(fileno))
        self._chown_common(path, uid, gid)