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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 clean(self):
 """drop regularization and prior information observation from the jco """

        if self.pst_arg is None:
            self.logger.statement("linear_analysis.clean(): not pst object")
            return
        if not self.pst.estimation and self.pst.nprior > 0:
            self.drop_prior_information()