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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 _cutoff(self, coeffs, vscale):
 """ Compute cutoff index after which the coefficients are deemed negligible. """

        bnd = self._threshold(vscale)
        inds  = np.nonzero(abs(coeffs) >= bnd)
        if len(inds[0]):
            N = inds[0][-1]
        else:
            N = 0
        return N+1