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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 fitted(self, fid=0):
 """Test if enough Levenberg-Marquardt loops have been done. It returns True if no improvement possible. :param fid: the id of the sub-fitter (numerical) """

        self._checkid(fid)
        return not (self._fitids[fid]["fit"] > 0
                    or self._fitids[fid]["fit"] < -0.001)