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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 _set_final_freeness(self, flag):
 """ Sets the freedom of the final chunk. Since no proper chunk follows the final chunk, the heap itself manages this. Nonetheless, for now it is implemented as if an additional chunk followed the final chunk. """

        if flag:
            self.state.memory.store(self.heap_base + self.heap_size - self._chunk_size_t_size, ~CHUNK_P_MASK)
        else:
            self.state.memory.store(self.heap_base + self.heap_size - self._chunk_size_t_size, CHUNK_P_MASK)