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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 try_read_prev(self, address, size):
 """Try to read previous memory content at specified address. If any location was not written before, it returns a tuple (False, None). Otherwise, it returns (True, memory content). """

        value = 0x0

        for i in range(0, size):
            addr = address + i

            if addr in self.__memory_prev:
                _, val_byte = self.__try_read_byte_prev(addr)
                value |= val_byte << (i * 8)
            else:
                return False, None

        return True, value