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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 fit(self):
 """Fit MCMC AgeDepthModel"""

        self._mcmcfit = self.mcmcsetup.run()
        self._mcmcfit.burnin(self.burnin)
        dmin = min(self._mcmcfit.depth_segments)
        dmax = max(self._mcmcfit.depth_segments)
        self._thick = (dmax - dmin) / len(self.mcmcfit.depth_segments)
        self._depth = np.arange(dmin, dmax + 0.001)
        self._age_ensemble = np.array([self.agedepth(d=dx) for dx in self.depth])