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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 get_discrete_dims(self):
 """ Returns the dimension of the discrete components of the domain. """

        discrete_dims = []
        for i in range(self.dimensionality):
            if self.space_expanded[i].type == 'discrete':
                discrete_dims += [i]
        return discrete_dims