def identify_tracks_to_add(client, source_playlist, destination_playlist):
    """
    Examines the track list of `destination_playlist` to determine if tracks in `source_playlist` are present. Tracks
    from `source_playlist` that are not present in `destination_playlist` are added to a list of tracks to be later
    added to `destination_playlist`.

    :param client:
    :param source_playlist:
    :param destination_playlist:
    :return:
    """
    identified_tracks = []

    if source_playlist is not None:
        source_playlist_tracks = client.get_playlist_tracks(source_playlist)

        for track in source_playlist_tracks:
            track_in_destination_playlist = client.search_playlist(track['track']['id'], destination_playlist)

            if not track_in_destination_playlist:
                identified_tracks.append(track['track']['uri'])

    return identified_tracks