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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 _populate_audio_file(self):
 """ Create the ``self.audio_file`` object by reading the audio file at ``self.audio_file_path_absolute``. """

        self.log(u"Populate audio file...")
        if self.audio_file_path_absolute is not None:
            self.log([u"audio_file_path_absolute is '%s'", self.audio_file_path_absolute])
            self.audio_file = AudioFile(
                file_path=self.audio_file_path_absolute,
                logger=self.logger
            )
            self.audio_file.read_properties()
        else:
            self.log(u"audio_file_path_absolute is None")
        self.log(u"Populate audio file... done")