Add script to remove duplicates, from https://gist.github.com/shuichinet/8159878#file-gpm_cleaner-py.

.gitignore

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+/venv

gpm_cleaner.py

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+#!/usr/bin/env python
+
+from gmusicapi import Mobileclient
+from getpass import getpass
+
+client = Mobileclient()
+client.login( raw_input( "Username: " ), getpass() )
+
+print "Getting all songs ..."
+all_songs = client.get_all_songs()
+new_songs = {}
+old_songs = {}
+
+for song in all_songs:
+    song_id = song.get('id')
+    timestamp = song.get('recentTimestamp')
+    
+    key = "%s: %d-%02d %s" % ( song.get('album'), song.get('discNumber'), song.get('trackNumber'), song.get('title') )
+    
+    if key in new_songs:
+        if new_songs[key]['timestamp'] < timestamp:
+            old_songs[key] = new_songs[key]
+            new_songs[key] = { 'id': song_id, 'timestamp': timestamp }
+        else:
+            old_songs[key] = { 'id': song_id, 'timestamp': timestamp }
+    
+    new_songs[key] = { 'id': song_id, 'timestamp': timestamp }
+
+if len( old_songs ):
+    print "Duplicate songs"
+    
+    old_song_ids = []
+    
+    for key in sorted( old_songs.keys() ):
+        old_song_ids.append( old_songs[key]['id'] )
+        print "    " + key.encode('utf-8')
+    
+    if raw_input( "Delete duplicate songs? (y, n): ") is 'y':
+        print "Deleting songs ..."
+        client.delete_songs( old_song_ids )
+else:
+    print "No duplicate songs"