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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 residuals(self, pars, x, y, order):
 """ Residual of Fourier Series. Parameters pars : array_like Fourier series parameters. x : array_like An array of date. y : array_like An array of true values to fit. order : int An order of Fourier Series. """


        return y - self.fourier_series(pars, x, order)