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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 anonymized_formula(self):
 """ An anonymized formula. Appends charge to the end of anonymized composition """

        anon_formula = super().anonymized_formula
        chg = self._charge
        chg_str = ""
        if chg > 0:
            chg_str += ("{}{}".format('+', str(int(chg))))
        elif chg < 0:
            chg_str += ("{}{}".format('-', str(int(np.abs(chg)))))
        return anon_formula + chg_str