======================== unified (from filesystem) ========================
                                         'bitrate'  '192.0'
                                        'duration'  '171'
                                          'artist'  'Pop Stoneman'
                                     'text_people'  ''
                                         'release'  'Classic Mountain Songs from Smithsonian Folkways (2002, Smithsonian Folkways)'
                                           'title'  'Wreck of the Number Nine'
                                           'quals'  ("['Q-HAP-3', 'Q-UNU-2', 'Q-LOCALNESS-3', 'Q-OLDST-1', 'Q-JZFKS-1', "
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 "'q-chart-1', 'q-drums-1', 'q-other-3', 'q-piano-1', 'q-vocals-4', "
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                                      'lastfmtags'  "['folk', 'appalachia', 'americana']"
                             'musicbrainz_albumid'  ''
                       'musicbrainz_albumartistid'  ''
                            'musicbrainz_artistid'  ''
                             'musicbrainz_trackid'  ''
                                     'tracknumber'  '21'
                                      'tracktotal'  ''
                                            'date'  '2002'
                                        'comments'  ''
                                           'genre'  'ifs-songwriter-folk;loc-namerica'
                                             'bpm'  '131.328'
                                             'key'  '9A'
                                        'acoustid'  ''
rest: ''

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

'TALB' (Album/Movie/Show title)                     'Classic Mountain Songs from Smithsonian Folkways (2002, Smithsonian Folkways)'
'TBPM' (BPM (beats per minute))                     '131.328'
'TCON' (Content type, a.k.a. Genre)                 ['ifs-songwriter-folk', 'loc-namerica']
'TDRC' (Recording time)                             '2002'
'TIT2' (Title/songname/content description)         'Wreck of the Number Nine'
'TKEY' (Initial key)                                '9A'
'TPE1' (Lead performer(s)/Soloist(s))               'Pop Stoneman'
'TPE2' (Band/orchestra/accompaniment)               'Various Artists / Various Artists'
'TPOS' (Part of a set)                              '1/1'
'TPUB' (Publisher)                                  'Smithsonian Folkways'
'TRCK' (Track number/Position in set)               '21'
'TXXX:ALBUMARTIST'                                  'Various Artists'
'TXXX:Q-HAP'                                        '3'
'TXXX:Q-HHRNBTT'                                    '1'
'TXXX:Q-JZFKS'                                      '1'
'TXXX:Q-LOCALNESS'                                  '3'
'TXXX:Q-OLDST'                                      '1'
'TXXX:Q-UNU'                                        '2'
'TXXX:lastfmtags'                                   ['folk', 'appalachia', 'americana']
'TXXX:q-bass'                                       '1'
'TXXX:q-busy'                                       '3'
'TXXX:q-chart'                                      '1'
'TXXX:q-drums'                                      '1'
'TXXX:q-grit'                                       '2'
'TXXX:q-mixbeat'                                    '1'
'TXXX:q-other'                                      '3'
'TXXX:q-piano'                                      '1'
'TXXX:q-play'                                       '2'
'TXXX:q-syn'                                        '1'
'TXXX:q-vocals'                                     '4'
'TXXX:replaygain_track_gain'                        '+0.47 dB'
'TXXX:replaygain_track_peak'                        '0.450412'

========================== row from database ==========================
                                              'id'  471522
                                            'path'  /data/Music/Bulk/00localcharacter/VA. World 1： Trad/Classic Mountain Songs from Smithsonian Folkways (Smithsonian Folkways, 2002) [192k]/21 Wreck of the Number Nine.mp3
                                         'working'  None
                                         'bitrate'  192
                                    'duration_sec'  171
                                           'genre'  ifs-songwriter-folk;loc-namerica
                                        'filesize'  4124996
                                           'mtime'  1621629868
                                   'redo_metaread'  0
                                        'rest_str'   00localcharacter VA. World 1： Trad (Smithsonian Folkways, 2002) [192k] 21 ifs songwriter folk;loc namerica
                                      'tag_artist'  Pop Stoneman
                                     'tag_release'  Classic Mountain Songs from Smithsonian Folkways (2002, Smithsonian Folkways)
                                       'tag_title'  Wreck of the Number Nine
                                             'bpm'  131.328
                                    'search_title'  'nine':5 'number':4 'of':2 'the':3 'wreck':1
                                   'search_artist'  'pop':1 'stoneman':2
                                  'search_release'  '2002':7,8 'classic':1 'folkways':6,9 'from':4 'mountain':2 'smithsonian':5 'songs':3
                                     'search_rest'  '1':4,5,6 '192k':14,15 '2002':12,13 '21':16 'folk':19,21 'folkways':10,11 'ifs':17 'loc':20,22 'namerica':23 'smithsonian':8,9 'songwriter':18 'trad':7 'va':1,2 'world':3
                                    'search_combo'  '1':20,21,22 '192k':30,31 '2002':14C,15C,28,29 '21':32 'classic':8C 'folk':35,37 'folkways':13C,16C,26,27 'from':11C 'ifs':33 'loc':36,38 'mountain':9C 'namerica':39 'nine':5A 'number':4A 'of':2A 'pop':6B 'smithsonian':12C,24,25 'songs':10C 'songwriter':34 'stoneman':7B 'the':3A 'trad':23 'va':17,18 'world':19 'wreck':1A
                                    'tag_tracknum'  21
                                      'num_images'  0
                                             'key'  9A
                                           'quals'  ['Q-HHRNBTT-1', 'q-vocals-4', 'Q-LOCALNESS-3', 'q-piano-1', 'q-mixbeat-1', 'q-play-2', 'Q-OLDST-1', 'Q-UNU-2', 'Q-JZFKS-1', 'q-busy-3', 'q-drums-1', 'q-syn-1', 'q-chart-1', 'q-other-3', 'Q-HAP-3', 'q-bass-1', 'q-grit-2']
                                      'lastfmtags'  ['folk', 'appalachia', 'americana']
                                        'tag_date'  2002
                                     'discogstags'  []

============================== file details ==============================
                                           'mtime'  1621629867.7857213  (2021-05-21 22:44:27)
                             'size'  4124996