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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_axis_label(self, dim):
 """Return the channel id from a dimension, if applicable."""

        if u(dim[:-1]).isdecimal():
            n = len(self.channel_ids)
            return str(self.channel_ids[int(dim[:-1]) % n]) + dim[-1]
        else:
            return dim