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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 _surface(self, T):
 """Generic equation for the surface tension Parameters T : float Temperature, [K] Returns ------- σ : float Surface tension, [N/m] Notes ----- Need a _surf dict in the derived class with the parameters keys: sigma: coefficient exp: exponent """

        tau = 1-T/self.Tc
        sigma = 0
        for n, t in zip(self._surf["sigma"], self._surf["exp"]):
            sigma += n*tau**t
        return sigma