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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 analysis(self):
 """Get musical analysis of the song using the librosa library """

        if self._analysis is not None:
            return self._analysis

        if self.cache_dir is not None:
            path = os.path.join(self.cache_dir, self.checksum)
            try:
                if self.refresh_cache: raise IOError
                with open(path + '.pickle', 'rb') as pickle_file:
                    self._analysis = pickle.load(pickle_file)
            except IOError:
                self._analysis = librosa_analysis.analyze_frames(self.all_as_mono(), self.samplerate)
                with open(path + '.pickle', 'wb') as pickle_file:
                    pickle.dump(self._analysis, pickle_file, pickle.HIGHEST_PROTOCOL)
        else:
            self._analysis = librosa_analysis.analyze_frames(self.all_as_mono(), self.samplerate)
        return self._analysis