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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 join(self, vals):
 """ Either return the non-list value or raise an Exception. Arguments: vals - a list of values to process """

        if len(vals) == 1:
            return vals[0]
        raise Exception(
            "Too many values for {}:{}".format(self._component_name, self._key)
        )