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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 append(self, sc):
 """ Add scale 'sc' and remove any previous scales that cover the same aesthetics """

        ae = sc.aesthetics[0]
        cover_ae = self.find(ae)
        if any(cover_ae):
            warn(_TPL_DUPLICATE_SCALE.format(ae), PlotnineWarning)
            idx = cover_ae.index(True)
            self.pop(idx)
        # super() does not work well with reloads
        list.append(self, sc)