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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 num_channels(self):
 """ Get the number of channels in the input generators. """

        if(self.inspect_value('index') is None):
            if(len(self.generators)>0):
                return self.generators[0].num_channels()
            return 0

        return self.get_current_generator().num_channels()