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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 add_cohp(self, label, cohp):
 """ Adds a COHP for plotting. Args: label: Label for the COHP. Must be unique. cohp: COHP object. """

        energies = cohp.energies - cohp.efermi if self.zero_at_efermi \
            else cohp.energies
        populations = cohp.get_cohp()
        int_populations = cohp.get_icohp()
        self._cohps[label] = {"energies": energies, "COHP": populations,
                              "ICOHP": int_populations, "efermi": cohp.efermi}