======================== unified (from filesystem) ========================
                                         'bitrate'  '128.0'
                                        'duration'  '153'
                                          'artist'  'Brass Band (Oldest known band recording)'
                                     'text_people'  ''
                                         'release'  ''
                                           'title'  "Issler's Orchestra - Fifth Regiment March"
                                           'quals'  ("['Q-HAP-3', 'Q-JZFKS-2', 'Q-LOCALNESS-1', 'Q-UNU-1', 'Q-HHRNBTT-1', "
 "'Q-OLDST-1', 'q-syn-1', 'q-bass-1', 'q-busy-3', 'q-grit-1', 'q-play-2', "
 "'q-chart-2', 'q-drums-2', 'q-other-4', 'q-piano-1', 'q-vocals-3', "
 "'q-mixbeat-1']")
                             'musicbrainz_albumid'  ''
                       'musicbrainz_albumartistid'  ''
                            'musicbrainz_artistid'  ''
                             'musicbrainz_trackid'  ''
                                     'tracknumber'  ''
                                      'tracktotal'  ''
                                            'date'  '1989'
                                        'comments'  ''
                                           'genre'  'prerock-band'
                                             'bpm'  '114.7'
                                             'key'  '6B'
                                        'acoustid'  ''
rest: ''

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

'TBPM' (BPM (beats per minute))                     '114.7'
'TCON' (Content type, a.k.a. Genre)                 'prerock-band'
'TDRC' (Recording time)                             '1989'
'TIT2' (Title/songname/content description)         "Issler's Orchestra - Fifth Regiment March"
'TKEY' (Initial key)                                '6B'
'TPE1' (Lead performer(s)/Soloist(s))               'Brass Band (Oldest known band recording)'
'TXXX:Mp3gain_minmax'                               '129,167'
'TXXX:Mp3gain_undo'                                 '+005,+005,N'
'TXXX:Q-HAP'                                        '3'
'TXXX:Q-HHRNBTT'                                    '1'
'TXXX:Q-JZFKS'                                      '2'
'TXXX:Q-LOCALNESS'                                  '1'
'TXXX:Q-OLDST'                                      '1'
'TXXX:Q-UNU'                                        '1'
'TXXX:q-bass'                                       '1'
'TXXX:q-busy'                                       '3'
'TXXX:q-chart'                                      '2'
'TXXX:q-drums'                                      '2'
'TXXX:q-grit'                                       '1'
'TXXX:q-mixbeat'                                    '1'
'TXXX:q-other'                                      '4'
'TXXX:q-piano'                                      '1'
'TXXX:q-play'                                       '2'
'TXXX:q-syn'                                        '1'
'TXXX:q-vocals'                                     '3'
'TXXX:replaygain_track_gain'                        '+1.81 dB'
'TXXX:replaygain_track_peak'                        '0.426445'

========================== row from database ==========================
                                              'id'  1516622
                                            'path'  /data/Music/Bulk/00exnnpjpsprgttidm/Wax Cylinder／very old recordings： 1878-1920 [wma／32k]/1889 - Brass Band (Oldest known band recording) - Issler_s Orchestra - Fifth Regiment March.mp3
                                         'working'  None
                                         'bitrate'  128
                                    'duration_sec'  153
                                           'genre'  prerock-band
                                        'filesize'  2458826
                                           'mtime'  1620561427
                                   'redo_metaread'  0
                                        'rest_str'   00exnnpjpsprgttidm Wax Cylinder／very old recordings： 1878 1920 [wma／32k] 1889 Issler_s prerock
                                      'tag_artist'  Brass Band (Oldest known band recording)
                                     'tag_release'  None
                                       'tag_title'  Issler's Orchestra - Fifth Regiment March
                                             'bpm'  114.7
                                    'search_title'  'fifth':5 'issler':1 'isslers':3 'march':7 'orchestra':4 'regiment':6 's':2
                                   'search_artist'  'band':2 'brass':1 'known':5 'oldest':3,4 'recording':6,7
                                  'search_release'  
                                     'search_rest'  '1878':11 '1889':20 '1920':12 '32k':14,16,18 'cylinder':2,4 'cylindervery':6 'issler':21 'old':7 'prerock':23 'recordings':8,9,10 's':22 'very':3,5 'wax':1 'wma':13,15,17 'wma32k':19
                                    'search_combo'  '1878':25 '1889':34 '1920':26 '32k':28,30,32 'band':9B 'brass':8B 'cylinder':16,18 'cylindervery':20 'fifth':5A 'issler':1A,35 'isslers':3A 'known':12B 'march':7A 'old':21 'oldest':10B,11B 'orchestra':4A 'prerock':37 'recording':13B,14B 'recordings':22,23,24 'regiment':6A 's':2A,36 'very':17,19 'wax':15 'wma':27,29,31 'wma32k':33
                                    'tag_tracknum'  None
                                      'num_images'  0
                                             'key'  6B
                                           'quals'  ['Q-HHRNBTT-1', 'q-vocals-3', 'Q-LOCALNESS-1', 'q-piano-1', 'q-mixbeat-1', 'q-play-2', 'Q-OLDST-1', 'Q-UNU-1', 'Q-JZFKS-2', 'q-busy-3', 'q-drums-2', 'q-syn-1', 'q-chart-2', 'q-other-4', 'Q-HAP-3', 'q-bass-1', 'q-grit-1']
                                      'lastfmtags'  []
                                        'tag_date'  1989
                                     'discogstags'  []

============================== file details ==============================
                                           'mtime'  1620561427.2736077  (2021-05-09 13:57:07)
                             'size'  2458826