======================== unified (from filesystem) ========================
                                         'bitrate'  '128.0'
                                        'duration'  '181'
                                          'artist'  'Billy Golden'
                                     'text_people'  ''
                                         'release'  ''
                                           'title'  'The Mocking Bird 1897'
                                           'quals'  ("['Q-HAP-3', 'Q-UNU-1', 'Q-LOCALNESS-1', 'Q-JZFKS-2', 'Q-HHRNBTT-1', "
 "'Q-OLDST-1', 'q-syn-1', 'q-bass-1', 'q-busy-3', 'q-grit-1', 'q-play-3', "
 "'q-chart-2', 'q-drums-1', 'q-other-3', 'q-piano-1', 'q-vocals-4', "
 "'q-mixbeat-1']")
                                      'lastfmtags'  "['fun', '1890 1900', '19th century', 'minstrel', 'acoustic era']"
                             'musicbrainz_albumid'  ''
                       'musicbrainz_albumartistid'  ''
                            'musicbrainz_artistid'  ''
                             'musicbrainz_trackid'  ''
                                     'tracknumber'  ''
                                      'tracktotal'  ''
                                            'date'  '1897'
                                        'comments'  ''
                                           'genre'  'prerock-instrumental;mi-whistling'
                                             'bpm'  '119.7'
                                             'key'  '3A'
                                        'acoustid'  ''
rest: ''

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

'APIC:'                                             type PictureType.COVER_FRONT (Cover (front)) b''
                                     
'TBPM' (BPM (beats per minute))                     '119.7'
'TCON' (Content type, a.k.a. Genre)                 ['prerock-instrumental', 'mi-whistling']
'TDRC' (Recording time)                             '1897'
'TIT2' (Title/songname/content description)         'The Mocking Bird 1897'
'TKEY' (Initial key)                                '3A'
'TPE1' (Lead performer(s)/Soloist(s))               'Billy Golden'
'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'                                   ['fun', '1890 1900', '19th century', 'minstrel', 'acoustic era']
'TXXX:q-bass'                                       '1'
'TXXX:q-busy'                                       '3'
'TXXX:q-chart'                                      '2'
'TXXX:q-drums'                                      '1'
'TXXX:q-grit'                                       '1'
'TXXX:q-mixbeat'                                    '1'
'TXXX:q-other'                                      '3'
'TXXX:q-piano'                                      '1'
'TXXX:q-play'                                       '3'
'TXXX:q-syn'                                        '1'
'TXXX:q-vocals'                                     '4'
'TXXX:replaygain_track_gain'                        '+4.05 dB'
'TXXX:replaygain_track_peak'                        '0.366919'

========================== row from database ==========================
                                              'id'  515114
                                            'path'  /data/Music/Bulk/00exnnpjpsprgttidm/Wax Cylinder／very old recordings： 1878-1920 [wma／32k]/1897 - Billy Golden - The Mocking Bird.mp3
                                         'working'  None
                                         'bitrate'  128
                                    'duration_sec'  181
                                           'genre'  prerock-instrumental;mi-whistling
                                        'filesize'  3298142
                                           'mtime'  1620527944
                                   'redo_metaread'  0
                                        'rest_str'   00exnnpjpsprgttidm Wax Cylinder／very recordings： 1878 1920 [wma／32k] prerock instrumental;mi whistling
                                      'tag_artist'  Billy Golden
                                     'tag_release'  None
                                       'tag_title'  The Mocking Bird 1897
                                             'bpm'  119.7
                                    'search_title'  '1897':4 'bird':3 'mocking':2 'the':1
                                   'search_artist'  'billy':1 'golden':2
                                  'search_release'  
                                     'search_rest'  '1878':10 '1920':11 '32k':13,15,17 'cylinder':2,4 'cylindervery':6 'instrumental':20,22 'mi':21,23 'prerock':19 'recordings':7,8,9 'very':3,5 'wax':1 'whistling':24 'wma':12,14,16 'wma32k':18
                                    'search_combo'  '1878':16 '1897':4A '1920':17 '32k':19,21,23 'billy':5B 'bird':3A 'cylinder':8,10 'cylindervery':12 'golden':6B 'instrumental':26,28 'mi':27,29 'mocking':2A 'prerock':25 'recordings':13,14,15 'the':1A 'very':9,11 'wax':7 'whistling':30 'wma':18,20,22 'wma32k':24
                                    'tag_tracknum'  None
                                      'num_images'  1
                                             'key'  3A
                                           'quals'  ['Q-HHRNBTT-1', 'q-vocals-4', 'Q-LOCALNESS-1', 'q-piano-1', 'q-mixbeat-1', 'q-play-3', 'Q-OLDST-1', 'Q-UNU-1', 'Q-JZFKS-2', 'q-busy-3', 'q-drums-1', 'q-syn-1', 'q-chart-2', 'q-other-3', 'Q-HAP-3', 'q-bass-1', 'q-grit-1']
                                      'lastfmtags'  ['fun', '1890 1900', '19th century', 'minstrel', 'acoustic era']
                                        'tag_date'  1897
                                     'discogstags'  []

============================== file details ==============================
                                           'mtime'  1620527944.228934  (2021-05-09 04:39:04)
                             'size'  3298142