======================== unified (from filesystem) ========================
                                         'bitrate'  '185.584'
                                        'duration'  '237'
                                          'artist'  'Tschaikovski'
                                     'text_people'  ''
                                         'release'  ''
                                           'title'  'Serenade for Strings: Waltz'
                                           'quals'  ("['Q-HAP-3', 'Q-LOCALNESS-1', 'Q-JZFKS-1', 'Q-UNU-1', 'Q-HHRNBTT-1', "
 "'Q-OLDST-1', 'q-syn-1', 'q-bass-1', 'q-busy-2', 'q-grit-2', 'q-play-3', "
 "'q-chart-3', 'q-drums-1', 'q-other-4', 'q-piano-1', 'q-vocals-1', "
 "'q-mixbeat-1']")
                                      'lastfmtags'  "['classical', 'romantic', 'russian', 'composers', 'instrumental']"
                             'musicbrainz_albumid'  ''
                       'musicbrainz_albumartistid'  ''
                            'musicbrainz_artistid'  ''
                             'musicbrainz_trackid'  ''
                                     'tracknumber'  '3'
                                      'tracktotal'  ''
                                            'date'  ''
                                        'comments'  ''
                                           'genre'  'prerock-classical or classical instruments'
                                             'bpm'  '135.0'
                                             'key'  '10B'
                                        'acoustid'  ''
rest: ''

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

'MCDI' (Music CD identifier)                        MCDI(data=b'\x00r\x01\r\x00\x10\x01\x00\x00\x00\x00!\x00\x10\x02\x00\x00\x00E\x8b\x00\x10\x03\x00\x00\x00\xa5\n\x00\x10\x04\x00\x00\x00\xeb\x8c\x00\x10\x05\x00\x00\x019F\x00\x10\x06\x00\x00\x01\xca_\x00\x10\x07\x00\x00\x02\x00I\x00\x10\x08\x00\x00\x02m\xb6\x00\x10\t\x00\x00\x02\xc7\xc2\x00\x10\n\x00\x00\x03\x03\xb1\x00\x10\x0b\x00\x00\x03U7\x00\x10\x0c\x00\x00\x03\xc5{\x00\x10\r\x00\x00\x04\x157\x00\x10\xaa\x00\x00\x04\x85\xf1')
'TBPM' (BPM (beats per minute))                     '135.0'
'TCON' (Content type, a.k.a. Genre)                 'prerock-classical or classical instruments'
'TENC' (Encoded by)                                 'Greg'
'TIT2' (Title/songname/content description)         'Serenade for Strings: Waltz'
'TKEY' (Initial key)                                '10B'
'TPE1' (Lead performer(s)/Soloist(s))               'Tschaikovski'
'TRCK' (Track number/Position in set)               '3'
'TSSE' (Software/Hardware and settings used for encoding)  'Audiograbber 1.80, LAME dll 3.92, VBR 2, Stereo, High quality'
'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'                                   ['classical', 'romantic', 'russian', 'composers', 'instrumental']
'TXXX:q-bass'                                       '1'
'TXXX:q-busy'                                       '2'
'TXXX:q-chart'                                      '3'
'TXXX:q-drums'                                      '1'
'TXXX:q-grit'                                       '2'
'TXXX:q-mixbeat'                                    '1'
'TXXX:q-other'                                      '4'
'TXXX:q-piano'                                      '1'
'TXXX:q-play'                                       '3'
'TXXX:q-syn'                                        '1'
'TXXX:q-vocals'                                     '1'
'TXXX:replaygain_track_gain'                        '+2.36 dB'
'TXXX:replaygain_track_peak'                        '0.421340'

========================== row from database ==========================
                                              'id'  1214289
                                            'path'  /data/Music/Bulk/00instruments-classical/Tchaikovski, P.I/Tschaikovsi, Pjotr - 03 - Serenade for Strings- Waltz.mp3
                                         'working'  None
                                         'bitrate'  185
                                    'duration_sec'  237
                                           'genre'  prerock-classical or classical instruments
                                        'filesize'  5505528
                                           'mtime'  1620561800
                                   'redo_metaread'  0
                                        'rest_str'   00instruments classical Tchaikovski, P.I Tschaikovsi, Pjotr 03 prerock classical classical instruments
                                      'tag_artist'  Tschaikovski
                                     'tag_release'  None
                                       'tag_title'  Serenade for Strings: Waltz
                                             'bpm'  135.0
                                    'search_title'  'for':2 'serenade':1 'strings':3,4 'waltz':5
                                   'search_artist'  'tschaikovski':1
                                  'search_release'  
                                     'search_rest'  '00instruments':1 'classical':2 'i':6 'instruments':12 'p':5 'pi':7 'pjotr':10 'prerock':11 'tchaikovski':3,4 'tschaikovsi':8,9
                                    'search_combo'  '00instruments':7 'classical':8 'for':2A 'i':12 'instruments':18 'p':11 'pi':13 'pjotr':16 'prerock':17 'serenade':1A 'strings':3A,4A 'tchaikovski':9,10 'tschaikovsi':14,15 'tschaikovski':6B 'waltz':5A
                                    'tag_tracknum'  3
                                      'num_images'  0
                                             'key'  10B
                                           'quals'  ['Q-HHRNBTT-1', 'q-vocals-1', 'Q-LOCALNESS-1', 'q-piano-1', 'q-mixbeat-1', 'q-play-3', 'Q-OLDST-1', 'Q-UNU-1', 'Q-JZFKS-1', 'q-busy-2', 'q-drums-1', 'q-syn-1', 'q-chart-3', 'q-other-4', 'Q-HAP-3', 'q-bass-1', 'q-grit-2']
                                      'lastfmtags'  ['classical', 'romantic', 'russian', 'composers', 'instrumental']
                                        'tag_date'  
                                     'discogstags'  []

============================== file details ==============================
                                           'mtime'  1620561799.6429062  (2021-05-09 14:03:19)
                             'size'  5505528