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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 nnz_obs_names(self):
 """get the non-zero weight observation names Returns ------- nnz_obs_names : list a list of non-zero weighted observation names """

        # nz_names = []
        # for w,n in zip(self.observation_data.weight,
        #                self.observation_data.obsnme):
        #     if w > 0.0:
        #         nz_names.append(n)
        obs = self.observation_data

        nz_names = list(obs.loc[obs.weight>0.0,"obsnme"])
        return nz_names