docs: def load_calibration(self):
          """Load factory calibration data from device."""
          registers = self.i2c_read_register(0xAA, 22)
          (
              self.cal['AC1'],
              self.cal['AC2'],
              self.cal['AC3'],
              self.cal['AC4'],
              self.cal['AC5'],
              self.cal['AC6'],
              self.cal['B1'],
              self.cal['B2'],
              self.cal['MB'],
              self.cal['MC'],
              self.cal['MD']
          ) = struct.unpack('>hhhHHHhhhhh', registers)