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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 greater_than_obs_constraints(self):
 """get the names of the observations that are listed as greater than inequality constraints. Zero- weighted obs are skipped Returns ------- pandas.Series : obsnme of obseravtions that are non-zero weighted greater than constraints """




        obs = self.observation_data
        gt_obs = obs.loc[obs.apply(lambda x: self._is_greater_const(x.obgnme) \
                                             and x.weight != 0.0,axis=1),"obsnme"]
        return gt_obs