def _is_primary_audio_channel(track):
    """
    Determines whether or not this is the "primary" audio track.

    audio may be structured in stereo where each channel occupies a separate
    track. This importer keeps stereo pairs ganged together as a single track.

    :param track: An XML track element.

    :return: A boolean ``True`` if this is the first track.
    """
    exploded_index = track.attrib.get('currentExplodedTrackIndex', '0')
    exploded_count = track.attrib.get('totalExplodedTrackCount', '1')
    return exploded_index == '0' or exploded_count == '1'
