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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 get_fmin(self):
 """ Returns the location where the posterior mean is takes its minimal value. """

        ps = self.model.param_array.copy()
        fmins = []
        for s in self.hmc_samples:
            if self.model._fixes_ is None:
                self.model[:] = s
            else:
                self.model[self.model._fixes_] = s
            self.model._trigger_params_changed()
            fmins.append(self.model.predict(self.model.X)[0].min())
        self.model.param_array[:] = ps
        self.model._trigger_params_changed()

        return fmins