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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 internal_temperature(self):
 """ Returns temperature in celsius C """

        temp_msb = self.bus.read_byte_data(AXP209_ADDRESS, INTERNAL_TEMPERATURE_MSB_REG)
        temp_lsb = self.bus.read_byte_data(AXP209_ADDRESS, INTERNAL_TEMPERATURE_LSB_REG)
        # MSB is 8 bits, LSB is lower 4 bits
        temp = temp_msb << 4 | temp_lsb & 0x0f
        # -144.7c -> 000h,	0.1c/bit	FFFh -> 264.8c
        return temp*0.1-144.7