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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 close_fd(self, fd):
 """Utility method to close an ``fd``. If ``fd`` is a file-like object, we close it directly; otherwise we use `os.close`. This method is provided for use by `IOLoop` subclasses (in implementations of ``IOLoop.close(all_fds=True)`` and should not generally be used by application code. .. versionadded:: 4.0 """

        try:
            try:
                fd.close()
            except AttributeError:
                os.close(fd)
        except OSError:
            pass