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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 addUsage_Label(self,usage_label):
        '''Appends one Usage_Label to usage_labels
        '''
        if isinstance(usage_label, Usage_Label):
            self.usage_labels.append(usage_label)
        else:
            raise (Usage_LabelError,
                   'usage_label Type should be Usage_Label, not %s' % type(
                    usage_label)
                   )