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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 linterp(self, setx, sety, x):
 """ Linear interp of model data values between time steps """

        if math.isnan(sety[0]) or math.isnan(setx[0]):
            return np.nan
        #if math.isnan(sety[0]):
        #    sety[0] = 0.
        #if math.isnan(sety[1]):
        #    sety[1] = 0.
        return sety[0] + (x - setx[0]) * ( (sety[1]-sety[0]) / (setx[1]-setx[0]) )