======================== unified (from filesystem) ========================
                                         'bitrate'  '128.0'
                                        'duration'  '177'
                                          'artist'  'Ada Jones & Len Spencer'
                                     'text_people'  ''
                                         'release'  'Victor-16294'
                                           'title'  "Si Perkins' Barn Dance (1909)"
                                           'quals'  ("['Q-HAP-3', 'Q-UNU-1', 'Q-LOCALNESS-1', 'Q-JZFKS-1', 'Q-HHRNBTT-1', "
 "'Q-OLDST-1', 'q-syn-1', 'q-bass-1', 'q-busy-3', 'q-grit-1', 'q-play-2', "
 "'q-chart-1', 'q-drums-1', 'q-other-3', 'q-piano-1', 'q-vocals-4', "
 "'q-mixbeat-1']")
                                      'lastfmtags'  "['jewish', 'vaudeville', 'cylinder', 'musical', 'early recordings']"
                             'musicbrainz_albumid'  ''
                       'musicbrainz_albumartistid'  ''
                            'musicbrainz_artistid'  ''
                             'musicbrainz_trackid'  ''
                                     'tracknumber'  '00'
                                      'tracktotal'  ''
                                            'date'  '1909'
                                        'comments'  ''
                                           'genre'  'prerock-vocal'
                                             'bpm'  '131.1'
                                             'key'  '9A'
                                        'acoustid'  ''
rest: ''

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

'APIC:'                                             type PictureType.COVER_FRONT (Cover (front)) b''
                                     
'COMM:MusicMatch_Preference:\x00\x00\x00'           'Excellent'
'COMM:MusicMatch_Tempo:\x00\x00\x00'                'None'
'TALB' (Album/Movie/Show title)                     'Victor-16294'
'TBPM' (BPM (beats per minute))                     '131.1'
'TCON' (Content type, a.k.a. Genre)                 'prerock-vocal'
'TDRC' (Recording time)                             '1909'
'TIT2' (Title/songname/content description)         "Si Perkins' Barn Dance (1909)"
'TKEY' (Initial key)                                '9A'
'TMED' (Media type)                                 'LIN'
'TPE1' (Lead performer(s)/Soloist(s))               'Ada Jones & Len Spencer'
'TRCK' (Track number/Position in set)               '00'
'TXXX:Q-HAP'                                        '3'
'TXXX:Q-HHRNBTT'                                    '1'
'TXXX:Q-JZFKS'                                      '1'
'TXXX:Q-LOCALNESS'                                  '1'
'TXXX:Q-OLDST'                                      '1'
'TXXX:Q-UNU'                                        '1'
'TXXX:lastfmtags'                                   ['jewish', 'vaudeville', 'cylinder', 'musical', 'early recordings']
'TXXX:q-bass'                                       '1'
'TXXX:q-busy'                                       '3'
'TXXX:q-chart'                                      '1'
'TXXX:q-drums'                                      '1'
'TXXX:q-grit'                                       '1'
'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'                        '+2.70 dB'
'TXXX:replaygain_track_peak'                        '0.608108'

========================== row from database ==========================
                                              'id'  1506047
                                            'path'  /data/Music/Bulk/00exnnpjpsprgttidm/Wax Cylinder／very old recordings： 1878-1920 [wma／32k]/1909 - Ada Jones - (L.Spencer) Si Perkins_ Barn Dance [speech.mp3
                                         'working'  None
                                         'bitrate'  128
                                    'duration_sec'  177
                                           'genre'  prerock-vocal
                                        'filesize'  3276972
                                           'mtime'  1621853377
                                   'redo_metaread'  0
                                        'rest_str'   00exnnpjpsprgttidm Wax Cylinder／very old recordings： 1878 1920 [wma／32k] (L.Spencer) Perkins_ [speech prerock vocal
                                      'tag_artist'  Ada Jones & Len Spencer
                                     'tag_release'  Victor-16294
                                       'tag_title'  Si Perkins' Barn Dance (1909)
                                             'bpm'  131.1
                                    'search_title'  '1909':6,7 'barn':4 'dance':5 'perkins':2,3 'si':1
                                   'search_artist'  'ada':1 'jones':2 'len':3 'spencer':4
                                  'search_release'  '16294':2 'victor':1 'victor16294':3
                                     'search_rest'  '1878':11 '1920':12 '32k':14,16,18 'cylinder':2,4 'cylindervery':6 'l':20 'lspencer':22 'old':7 'perkins':23 'prerock':26 'recordings':8,9,10 'speech':24,25 'spencer':21 'very':3,5 'vocal':27 'wax':1 'wma':13,15,17 'wma32k':19
                                    'search_combo'  '16294':13C '1878':25 '1909':6A,7A '1920':26 '32k':28,30,32 'ada':8B 'barn':4A 'cylinder':16,18 'cylindervery':20 'dance':5A 'jones':9B 'l':34 'len':10B 'lspencer':36 'old':21 'perkins':2A,3A,37 'prerock':40 'recordings':22,23,24 'si':1A 'speech':38,39 'spencer':11B,35 'very':17,19 'victor':12C 'victor16294':14C 'vocal':41 'wax':15 'wma':27,29,31 'wma32k':33
                                    'tag_tracknum'  None
                                      'num_images'  1
                                             'key'  9A
                                           'quals'  ['Q-HHRNBTT-1', 'q-vocals-4', 'Q-LOCALNESS-1', 'q-piano-1', 'q-mixbeat-1', 'q-play-2', 'Q-OLDST-1', 'Q-UNU-1', '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-1']
                                      'lastfmtags'  ['jewish', 'vaudeville', 'cylinder', 'musical', 'early recordings']
                                        'tag_date'  1909
                                     'discogstags'  []

============================== file details ==============================
                                           'mtime'  1621853376.7388668  (2021-05-24 12:49:36)
                             'size'  3276972