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

        self.observation_data.index = self.observation_data.obsnme
        groups = self.observation_data.groupby(
                self.observation_data.weight.apply(lambda x: x==0.0)).groups
        if True in groups:
            return list(self.observation_data.loc[groups[True],"obsnme"])
        else:
            return []