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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 get_over_current(self, channel):
        '''Reading over current status of power channel
        '''
        try:
            bit = self._ch_map[channel]['GPIOOC']['bit']
        except KeyError:
            raise ValueError('get_over_current() not supported for channel %s' % channel)
        return not self._get_power_gpio_value(bit)