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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_pidfile(self):
 """Closes and removes the PID file."""

        if self._pid_fd is not None:
            os.close(self._pid_fd)
        try:
            os.remove(self.pidfile)
        except OSError as ex:
            if ex.errno != errno.ENOENT:
                raise