======================== unified (from filesystem) ========================
                                         'bitrate'  '128.0'
                                        'duration'  '345'
                                          'artist'  'gregorian'
                                     'text_people'  ''
                                         'release'  ''
                                           'title'  'AudioTrack 05'
                                           'quals'  "['q-bass-3', 'q-drums-4', 'q-other-2', 'q-piano-1', 'q-vocals-3']"
                             'musicbrainz_albumid'  ''
                       'musicbrainz_albumartistid'  ''
                            'musicbrainz_artistid'  ''
                             'musicbrainz_trackid'  ''
                                     'tracknumber'  '5'
                                      'tracktotal'  '14'
                                            'date'  ''
                                        'comments'  ''
                                           'genre'  'Unknown'
                                             'bpm'  '92.0'
                                             'key'  '7A'
                                        'acoustid'  ''
rest: ''

======================== rawer (from filesystem) ========================

'TBPM' (BPM (beats per minute))                     '92.0'
'TCON' (Content type, a.k.a. Genre)                 'Unknown'
'TIT2' (Title/songname/content description)         'AudioTrack 05'
'TKEY' (Initial key)                                '7A'
'TPE1' (Lead performer(s)/Soloist(s))               'gregorian'
'TRCK' (Track number/Position in set)               '5/14'
'TXXX:q-bass'                                       '3'
'TXXX:q-drums'                                      '4'
'TXXX:q-other'                                      '2'
'TXXX:q-piano'                                      '1'
'TXXX:q-vocals'                                     '3'

========================== row from database ==========================
                                              'id'  1538464
                                            'path'  /data/Music/Other/PrevSet/[9amusing]/Gregorian/In The Air Tonight.mp3
                                         'working'  None
                                         'bitrate'  128
                                    'duration_sec'  345
                                           'genre'  Unknown
                                        'filesize'  5525165
                                           'mtime'  1662800495
                                   'redo_metaread'  0
                                        'rest_str'   PrevSet [9amusing] Gregorian In The Air Tonight Unknown
                                      'tag_artist'  gregorian
                                     'tag_release'  None
                                       'tag_title'  AudioTrack 05
                                             'bpm'  92.0
                                    'search_title'  'audio':2 'audiotrack':1 'track':3
                                   'search_artist'  'gregorian':1
                                  'search_release'  
                                     'search_rest'  '9amusing':2,3 'air':7 'gregorian':4 'in':5 'prev':10 'prevset':1 'set':11 'the':6 'tonight':8 'unknown':9
                                    'search_combo'  '9amusing':6,7 'air':11 'audio':2A 'audiotrack':1A 'gregorian':4B,8 'in':9 'prev':14 'prevset':5 'set':15 'the':10 'tonight':12 'track':3A 'unknown':13
                                    'tag_tracknum'  5
                                      'num_images'  0
                                             'key'  7A
                                           'quals'  ['q-bass-3', 'q-drums-4', 'q-other-2', 'q-piano-1', 'q-vocals-3']
                                      'lastfmtags'  []
                                        'tag_date'  
                                     'discogstags'  []

============================== file details ==============================
                                           'mtime'  1662800495.330624  (2022-09-10 11:01:35)
                             'size'  5525165