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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 _filtering_step(self, basename):
 """ Moves the audio file if the format is `wav` to `filtered` directory. Parameters basename : str A basename of `/home/random-guy/some-audio-file.wav` is `some-audio-file.wav` """

        name = ''.join(basename.split('.')[:-1])
        # May cause problems if wav is not less than 9 channels.
        if basename.split('.')[-1] == "wav":
            if self.get_verbosity():
                print("Found wave! Copying to {}/filtered/{}".format(
                    self.src_dir, basename))
            subprocess.Popen(["cp", "{}/{}.wav".format(self.src_dir, name),
                              "{}/filtered/{}.wav".format(self.src_dir, name)],
                             universal_newlines=True).communicate()