======================== unified (from filesystem) ========================
                                         'bitrate'  '160.0'
                                        'duration'  '239'
                                          'artist'  'Vernon Dalhart'
                                     'text_people'  ''
                                         'release'  'Edison  4424'
                                           'title'  'Molly On A Trolley (+ Betsy Lane Shepherd)'
                                           'quals'  ("['Q-HAP-3', 'Q-JZFKS-1', 'Q-LOCALNESS-2', 'Q-UNU-1', 'Q-HHRNBTT-1', "
 "'Q-OLDST-1', 'q-syn-1', 'q-bass-1', 'q-busy-3', 'q-grit-2', 'q-play-2', "
 "'q-chart-1', 'q-drums-1', 'q-other-1', 'q-piano-1', 'q-vocals-4', "
 "'q-mixbeat-1']")
                                      'lastfmtags'  "['old timey', 'country', 'all', 'americana', 'folk']"
                             'musicbrainz_albumid'  ''
                       'musicbrainz_albumartistid'  ''
                            'musicbrainz_artistid'  ''
                             'musicbrainz_trackid'  ''
                                     'tracknumber'  ''
                                      'tracktotal'  ''
                                            'date'  '1921'
                                        'comments'  ''
                                           'genre'  'prerock-americana'
                                             'bpm'  '114.028'
                                             'key'  '8A'
                                        'acoustid'  ''
rest: ''

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

'TALB' (Album/Movie/Show title)                     'Edison  4424'
'TBPM' (BPM (beats per minute))                     '114.028'
'TCON' (Content type, a.k.a. Genre)                 'prerock-americana'
'TDRC' (Recording time)                             '1921'
'TIT2' (Title/songname/content description)         'Molly On A Trolley (+ Betsy Lane Shepherd)'
'TKEY' (Initial key)                                '8A'
'TPE1' (Lead performer(s)/Soloist(s))               'Vernon Dalhart'
'TXXX:Q-HAP'                                        '3'
'TXXX:Q-HHRNBTT'                                    '1'
'TXXX:Q-JZFKS'                                      '1'
'TXXX:Q-LOCALNESS'                                  '2'
'TXXX:Q-OLDST'                                      '1'
'TXXX:Q-UNU'                                        '1'
'TXXX:lastfmtags'                                   ['old timey', 'country', 'all', 'americana', 'folk']
'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'                                      '1'
'TXXX:q-piano'                                      '1'
'TXXX:q-play'                                       '2'
'TXXX:q-syn'                                        '1'
'TXXX:q-vocals'                                     '4'
'TXXX:replaygain_track_gain'                        '+1.31 dB'
'TXXX:replaygain_track_peak'                        '0.550439'

========================== row from database ==========================
                                              'id'  1449520
                                            'path'  /data/Music/Bulk/00blues-jazz-exotica-oldies-country/00oldiepop/1921/Vernon Dalhart - Molly On A Trolley (+ Betsy Lane Shepherd) 1921.mp3
                                         'working'  None
                                         'bitrate'  160
                                    'duration_sec'  239
                                           'genre'  prerock-americana
                                        'filesize'  4783922
                                           'mtime'  1620559825
                                   'redo_metaread'  0
                                        'rest_str'   00blues jazz exotica oldies country 00oldiepop 1921 1921 prerock americana
                                      'tag_artist'  Vernon Dalhart
                                     'tag_release'  Edison  4424
                                       'tag_title'  Molly On A Trolley (+ Betsy Lane Shepherd)
                                             'bpm'  114.028
                                    'search_title'  'a':3 'betsy':5 'lane':6 'molly':1 'on':2 'shepherd':7,8 'trolley':4
                                   'search_artist'  'dalhart':2 'vernon':1
                                  'search_release'  '4424':2 'edison':1
                                     'search_rest'  '00oldiepop':5 '1921':6 'americana':8 'country':4 'exotica':2 'jazz':1 'oldies':3 'prerock':7
                                    'search_combo'  '00oldiepop':17 '1921':18 '4424':12C 'a':3A 'americana':20 'betsy':5A 'country':16 'dalhart':10B 'edison':11C 'exotica':14 'jazz':13 'lane':6A 'molly':1A 'oldies':15 'on':2A 'prerock':19 'shepherd':7A,8A 'trolley':4A 'vernon':9B
                                    'tag_tracknum'  None
                                      'num_images'  0
                                             'key'  8A
                                           'quals'  ['Q-HHRNBTT-1', 'q-vocals-4', 'Q-LOCALNESS-2', '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-1', 'Q-HAP-3', 'q-bass-1', 'q-grit-2']
                                      'lastfmtags'  ['old timey', 'country', 'all', 'americana', 'folk']
                                        'tag_date'  1921
                                     'discogstags'  []

============================== file details ==============================
                                           'mtime'  1620559824.9554646  (2021-05-09 13:30:24)
                             'size'  4783922