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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_all_pwm(self, on, off):
 """Sets all PWM channels."""

        self.i2c.write8(ALL_LED_ON_L, on & 0xFF)
        self.i2c.write8(ALL_LED_ON_H, on >> 8)
        self.i2c.write8(ALL_LED_OFF_L, off & 0xFF)
        self.i2c.write8(ALL_LED_OFF_H, off >> 8)