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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 homogeneous_poisson(self):
 """ returns the homogeneous poisson ratio """

        return (1. - 2. / 3. * self.g_vrh / self.k_vrh) / \
               (2. + 2. / 3. * self.g_vrh / self.k_vrh)