======================== unified (from filesystem) ========================
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                                        'duration'  '111'
                                          'artist'  'Nelson Freire'
                                     'text_people'  'Chopin, Frederic'
                                         'release'  'Nodame Cantabile Best100'
                                           'title'  '24 Preludes, Op.28 - #21 in B-flat major - Cantabile'
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                                      'lastfmtags'  "['classical', 'piano', 'brazilian', 'classical piano', 'radiotsar approved']"
                                     'discogstags'  "['classical']"
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                                      'tracktotal'  '36'
                                            'date'  '1970'
                                        'comments'  ''
                                           'genre'  'prerock-classical or classical instruments'
                                             'bpm'  '137.7'
                                             'key'  '6B'
                                        'acoustid'  ''
rest: ''

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

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'TBPM' (BPM (beats per minute))                     '137.7'
'TCOM' (Composer)                                   'Chopin, Frederic'
'TCON' (Content type, a.k.a. Genre)                 'prerock-classical or classical instruments'
'TDRC' (Recording time)                             '1970'
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'TIT2' (Title/songname/content description)         '24 Preludes, Op.28 - #21 in B-flat major - Cantabile'
'TKEY' (Initial key)                                '6B'
'TPE1' (Lead performer(s)/Soloist(s))               'Nelson Freire'
'TPE2' (Band/orchestra/accompaniment)               'Various Artists'
'TPOS' (Part of a set)                              '8/8'
'TRCK' (Track number/Position in set)               '35/36'
'TXXX:Q-HAP'                                        '3'
'TXXX:Q-HHRNBTT'                                    '1'
'TXXX:Q-JZFKS'                                      '1'
'TXXX:Q-LOCALNESS'                                  '1'
'TXXX:Q-OLDST'                                      '1'
'TXXX:Q-PIANO'                                      '4'
'TXXX:Q-PLAY'                                       '3'
'TXXX:Q-UNU'                                        '1'
'TXXX:discogstags'                                  'classical'
'TXXX:lastfmtags'                                   ['classical', 'piano', 'brazilian', 'classical piano', 'radiotsar approved']
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'TXXX:q-drums'                                      '1'
'TXXX:q-grit'                                       '2'
'TXXX:q-mixbeat'                                    '1'
'TXXX:q-other'                                      '1'
'TXXX:q-syn'                                        '1'
'TXXX:q-vocals'                                     '1'
'TXXX:replaygain_track_gain'                        '+1.52 dB'
'TXXX:replaygain_track_peak'                        '0.842886'

========================== row from database ==========================
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                                            'path'  /data/Music/Bulk/00instruments-classical/Compilations/Nodame Cantabile Best100/8-35 24 Preludes, Op.28 - #21 in B-flat major - Cantabile.mp3
                                         'working'  None
                                         'bitrate'  192
                                    'duration_sec'  111
                                           'genre'  prerock-classical or classical instruments
                                        'filesize'  2723801
                                           'mtime'  1620574158
                                   'redo_metaread'  0
                                        'rest_str'   00instruments classical Compilations 35 prerock classical classical instruments
                                      'tag_artist'  Nelson Freire
                                     'tag_release'  Nodame Cantabile Best100
                                       'tag_title'  24 Preludes, Op.28 - #21 in B-flat major - Cantabile
                                             'bpm'  137.7
                                    'search_title'  '21':7,8 '24':1 '28':5 'b':10 'bflat':12 'cantabile':14 'flat':11 'in':9 'major':13 'op':4 'op28':6 'preludes':2,3
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                                  'search_release'  'best100':3 'cantabile':2 'nodame':1
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                                    'tag_tracknum'  35
                                      'num_images'  1
                                             'key'  6B
                                           'quals'  ['Q-HHRNBTT-1', 'q-vocals-1', 'Q-LOCALNESS-1', 'q-mixbeat-1', 'Q-PIANO-4', 'Q-OLDST-1', 'Q-UNU-1', 'Q-JZFKS-1', 'q-busy-2', 'q-drums-1', 'q-syn-1', 'q-chart-3', 'q-other-1', 'Q-HAP-3', 'Q-PLAY-3', 'q-bass-1', 'q-grit-2']
                                      'lastfmtags'  ['classical', 'piano', 'brazilian', 'classical piano', 'radiotsar approved']
                                        'tag_date'  1970
                                     'discogstags'  ['classical']

============================== file details ==============================
                                           'mtime'  1620574158.4652994  (2021-05-09 17:29:18)
                             'size'  2723801