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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 linear(self, fnct, x, y, sd=None, wt=1.0, fid=0):
 """Make a linear least squares solution. Makes a linear least squares solution for the points through the ordinates at the x values, using the specified fnct. The x can be of any dimension, depending on the number of arguments needed in the functional evaluation. The values should be given in the order: and m arguments. x should be a vector of m*n length; y (the observations) a vector of length n. :param fnct: the functional to fit :param x: the abscissa values :param y: the ordinate values :param sd: standard deviation of equations (one or more values used cyclically) :param wt: an optional alternate for `sd` :param fid: the id of the sub-fitter (numerical) """

        self._fit(fitfunc="linear", fnct=fnct, x=x, y=y, sd=sd, wt=wt, fid=fid)