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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 copy(self):
 """ Returns a copy of the distribution. Returns ------- LinearGaussianCPD: copy of the distribution Examples -------- 'Y' ['X1', 'X2', 'X3'] """

        copy_cpd = LinearGaussianCPD(self.variable, self.beta, self.variance,
                                     list(self.evidence))

        return copy_cpd