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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 create_region(self, key, state, is_stack, related_function_addr, endness, backer_dict=None):
 """ Create a new MemoryRegion with the region key specified, and store it to self._regions. :param key: a string which is the region key :param state: the SimState instance :param bool is_stack: Whether this memory region is on stack. True/False :param related_function_addr: Which function first creates this memory region. Just for reference. :param endness: The endianness. :param backer_dict: The memory backer object. :return: None """


        self._regions[key] = MemoryRegion(key,
                                          state=state,
                                          is_stack=is_stack,
                                          related_function_addr=related_function_addr,
                                          endness=endness,
                                          backer_dict=backer_dict,
                                          )