======================== unified (from filesystem) ========================
                                         'bitrate'  '64.0'
                                        'duration'  '143'
                                          'artist'  "Sousa's Band"
                                     'text_people'  ''
                                         'release'  ''
                                           'title'  'Yazoo Dance 1895.'
                                           '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-3', 'q-piano-1', 'q-vocals-4', "
 "'q-mixbeat-1']")
                                      'lastfmtags'  "['1900s', 'all', 'big band', '1890s', '1901']"
                             'musicbrainz_albumid'  ''
                       'musicbrainz_albumartistid'  ''
                            'musicbrainz_artistid'  ''
                             'musicbrainz_trackid'  ''
                                     'tracknumber'  ''
                                      'tracktotal'  ''
                                            'date'  '1895'
                                        'comments'  ''
                                           'genre'  'prerock-band'
                                             'bpm'  '102.3'
                                             'key'  '6A'
                                        'acoustid'  ''
rest: ''

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

'APIC:'                                             type PictureType.COVER_FRONT (Cover (front)) b''
                                     
'TBPM' (BPM (beats per minute))                     '102.3'
'TCON' (Content type, a.k.a. Genre)                 'prerock-band'
'TDRC' (Recording time)                             '1895'
'TIT2' (Title/songname/content description)         'Yazoo Dance 1895.'
'TKEY' (Initial key)                                '6A'
'TPE1' (Lead performer(s)/Soloist(s))               "Sousa's Band"
'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:lastfmtags'                                   ['1900s', 'all', 'big band', '1890s', '1901']
'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'                                      '3'
'TXXX:q-piano'                                      '1'
'TXXX:q-play'                                       '2'
'TXXX:q-syn'                                        '1'
'TXXX:q-vocals'                                     '4'
'TXXX:replaygain_track_gain'                        '+2.60 dB'
'TXXX:replaygain_track_peak'                        '0.688571'

========================== row from database ==========================
                                              'id'  1496959
                                            'path'  /data/Music/Bulk/00exnnpjpsprgttidm/Wax Cylinder／very old recordings： 1878-1920 [wma／32k]/1895 - Sousa_s Band - Yazoo Dance.mp3
                                         'working'  None
                                         'bitrate'  64
                                    'duration_sec'  143
                                           'genre'  prerock-band
                                        'filesize'  1185793
                                           'mtime'  1620561428
                                   'redo_metaread'  0
                                        'rest_str'   00exnnpjpsprgttidm Wax Cylinder／very old recordings： 1878 1920 [wma／32k] Sousa_s prerock band
                                      'tag_artist'  Sousa's Band
                                     'tag_release'  None
                                       'tag_title'  Yazoo Dance 1895.
                                             'bpm'  102.3
                                    'search_title'  '1895':3,4 'dance':2 'yazoo':1
                                   'search_artist'  'band':4 's':2 'sousa':1 'sousas':3
                                  'search_release'  
                                     'search_rest'  '1878':11 '1920':12 '32k':14,16,18 'band':23 'cylinder':2,4 'cylindervery':6 'old':7 'prerock':22 'recordings':8,9,10 's':21 'sousa':20 'very':3,5 'wax':1 'wma':13,15,17 'wma32k':19
                                    'search_combo'  '1878':19 '1895':3A,4A '1920':20 '32k':22,24,26 'band':8B,31 'cylinder':10,12 'cylindervery':14 'dance':2A 'old':15 'prerock':30 'recordings':16,17,18 's':6B,29 'sousa':5B,28 'sousas':7B 'very':11,13 'wax':9 'wma':21,23,25 'wma32k':27 'yazoo':1A
                                    'tag_tracknum'  None
                                      'num_images'  1
                                             'key'  6A
                                           '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-2', 'q-busy-3', 'q-drums-2', 'q-syn-1', 'q-chart-2', 'q-other-3', 'Q-HAP-3', 'q-bass-1', 'q-grit-1']
                                      'lastfmtags'  ['1900s', 'all', 'big band', '1890s', '1901']
                                        'tag_date'  1895
                                     'discogstags'  []

============================== file details ==============================
                                           'mtime'  1620561427.7639806  (2021-05-09 13:57:07)
                             'size'  1185793