======================== unified (from filesystem) ========================
                                         'bitrate'  '128.0'
                                        'duration'  '624'
                                          'artist'  'Johann Sebastian Bach'
                                     'text_people'  ''
                                         'release'  ''
                                           'title'  'Concert voor piano en orkest'
                                           'quals'  ("['Q-HAP-3', 'Q-JZFKS-1', 'Q-UNU-1', 'Q-LOCALNESS-2', 'Q-HHRNBTT-1', "
 "'Q-OLDST-1', 'Q-PLAY-3', 'q-syn-1', 'q-bass-1', 'q-busy-2', 'q-grit-2', "
 "'Q-PIANO-4', 'q-chart-3', 'q-drums-1', 'q-other-3', 'q-vocals-1', "
 "'q-mixbeat-1']")
                                      'lastfmtags'  "['instrumental', 'composers', 'baroque', 'german', 'classical']"
                             'musicbrainz_albumid'  ''
                       'musicbrainz_albumartistid'  ''
                            'musicbrainz_artistid'  ''
                             'musicbrainz_trackid'  ''
                                     'tracknumber'  ''
                                      'tracktotal'  ''
                                            'date'  ''
                                        'comments'  ''
                                           'genre'  'prerock-classical or classical instruments'
                                             'bpm'  '121.8'
                                             'key'  '4A'
                                        'acoustid'  ''
rest: ''

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

'TBPM' (BPM (beats per minute))                     '121.8'
'TCON' (Content type, a.k.a. Genre)                 'prerock-classical or classical instruments'
'TIT2' (Title/songname/content description)         'Concert voor piano en orkest'
'TKEY' (Initial key)                                '4A'
'TPE1' (Lead performer(s)/Soloist(s))               'Johann Sebastian Bach'
'TXXX:Q-HAP'                                        '3'
'TXXX:Q-HHRNBTT'                                    '1'
'TXXX:Q-JZFKS'                                      '1'
'TXXX:Q-LOCALNESS'                                  '2'
'TXXX:Q-OLDST'                                      '1'
'TXXX:Q-PIANO'                                      '4'
'TXXX:Q-PLAY'                                       '3'
'TXXX:Q-UNU'                                        '1'
'TXXX:lastfmtags'                                   ['instrumental', 'composers', 'baroque', 'german', 'classical']
'TXXX:q-bass'                                       '1'
'TXXX:q-busy'                                       '2'
'TXXX:q-chart'                                      '3'
'TXXX:q-drums'                                      '1'
'TXXX:q-grit'                                       '2'
'TXXX:q-mixbeat'                                    '1'
'TXXX:q-other'                                      '3'
'TXXX:q-syn'                                        '1'
'TXXX:q-vocals'                                     '1'
'TXXX:replaygain_track_gain'                        '+1.12 dB'
'TXXX:replaygain_track_peak'                        '0.725536'

========================== row from database ==========================
                                              'id'  1214108
                                            'path'  /data/Music/Bulk/00instruments-classical/Bach/bach_-_concert_voor_piano_en_orkest_-_glen_gould.mp3
                                         'working'  None
                                         'bitrate'  128
                                    'duration_sec'  624
                                           'genre'  prerock-classical or classical instruments
                                        'filesize'  9995640
                                           'mtime'  1620574129
                                   'redo_metaread'  0
                                        'rest_str'   00instruments classical bach_ _concert_voor_piano_en_orkest_ _glen_gould prerock classical classical instruments
                                      'tag_artist'  Johann Sebastian Bach
                                     'tag_release'  None
                                       'tag_title'  Concert voor piano en orkest
                                             'bpm'  121.8
                                    'search_title'  'concert':1 'en':4 'orkest':5 'piano':3 'voor':2
                                   'search_artist'  'bach':3 'johann':1 'sebastian':2
                                  'search_release'  
                                     'search_rest'  '00instruments':1 'bach':3 'classical':2 'concert':4 'en':7 'glen':9 'gould':10 'instruments':12 'orkest':8 'piano':6 'prerock':11 'voor':5
                                    'search_combo'  '00instruments':9 'bach':8B,11 'classical':10 'concert':1A,12 'en':4A,15 'glen':17 'gould':18 'instruments':20 'johann':6B 'orkest':5A,16 'piano':3A,14 'prerock':19 'sebastian':7B 'voor':2A,13
                                    'tag_tracknum'  None
                                      'num_images'  0
                                             'key'  4A
                                           'quals'  ['Q-HHRNBTT-1', 'q-vocals-1', 'Q-LOCALNESS-2', 'q-mixbeat-1', 'Q-PIANO-4', 'Q-OLDST-1', 'Q-UNU-1', 'Q-JZFKS-1', 'q-busy-2', 'q-drums-1', 'q-syn-1', 'q-chart-3', 'q-other-3', 'Q-HAP-3', 'Q-PLAY-3', 'q-bass-1', 'q-grit-2']
                                      'lastfmtags'  ['instrumental', 'composers', 'baroque', 'german', 'classical']
                                        'tag_date'  
                                     'discogstags'  []

============================== file details ==============================
                                           'mtime'  1620574128.835516  (2021-05-09 17:28:48)
                             'size'  9995640