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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 prior_groups(self):
 """get the prior info groups Returns ------- prior_groups : list a list of prior information groups """

        og = list(self.prior_information.groupby("obgnme").groups.keys())
        #og = list(map(pst_utils.SFMT, og))
        return og