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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_state(self, state):
 """Returns an exact copy of the provided state Implemented according to self.copy_strategy, one of * deepcopy : use copy.deepcopy (slow but reliable) * slice: use list slices (faster but only works if state is list-like) * method: use the state's copy() method """

        if self.copy_strategy == 'deepcopy':
            return copy.deepcopy(state)
        elif self.copy_strategy == 'slice':
            return state[:]
        elif self.copy_strategy == 'method':
            return state.copy()
        else:
            raise RuntimeError('No implementation found for ' +
                               'the self.copy_strategy "%s"' %
                               self.copy_strategy)