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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 encode(self, flo=None, fmt='WAV', subtype='PCM_16'):
 """ Return audio samples encoded as bytes given a particular audio format Args: flo (file-like):
 A file-like object to write the bytes to. If flo is not supplied, a new :class:`io.BytesIO` instance will be created and returned fmt (str):
 A libsndfile-friendly identifier for an audio encoding (detailed here: http://www.mega-nerd.com/libsndfile/api.html) subtype (str):
 A libsndfile-friendly identifier for an audio encoding subtype (detailed here: http://www.mega-nerd.com/libsndfile/api.html) Examples: 'RIFFx]\\x03\\x00WA' """

        flo = flo or BytesIO()
        with SoundFile(
                flo,
                mode='w',
                channels=self.channels,
                format=fmt,
                subtype=subtype,
                samplerate=self.samples_per_second) as f:

            if fmt == 'OGG':
                # KLUDGE: Trying to write too-large chunks to an ogg file seems
                # to cause a segfault in libsndfile
                # KLUDGE: This logic is very similar to logic in the OggVorbis
                # processing node, and should probably be factored into a common
                # location
                factor = 20
                chunksize = self.samples_per_second * factor
                for i in range(0, len(self), chunksize):
                    chunk = self[i: i + chunksize]
                    f.write(chunk)
            else:
                # write everything in one chunk
                f.write(self)

        flo.seek(0)
        return flo