Made cache_path and username optional (#567)

* Made cache_path and username optional

* Update readme and example

* Lint

* Lint

* Feedback / add warning

examples/my_top_tracks.py

@@ -1,16 +1,8 @@
 # Shows the top tracks for a user
 
-import sys
-
 import spotipy
 from spotipy.oauth2 import SpotifyOAuth
 
-if len(sys.argv) > 1:
-    username = sys.argv[1]
-else:
-    print("Usage: %s username" % (sys.argv[0],))
-    sys.exit()
-
 scope = 'user-top-read'
 sp = spotipy.Spotify(auth_manager=SpotifyOAuth(scope=scope))
 

examples/remove_specific_tracks_from_playlist.py

@@ -15,7 +15,7 @@ if len(sys.argv) > 2:
         track_ids.append({"uri": tid, "positions": [int(pos)]})
 else:
     print(
-        "Usage: %s username playlist_id track_id,pos track_id,pos ..." %
+        "Usage: %s playlist_id track_id,pos track_id,pos ..." %
         (sys.argv[0],))
     sys.exit()
 

examples/replace_tracks_in_playlist.py

@@ -10,7 +10,7 @@ if len(sys.argv) > 3:
     playlist_id = sys.argv[1]
     track_ids = sys.argv[2:]
 else:
-    print("Usage: %s username playlist_id track_id ..." % (sys.argv[0],))
+    print("Usage: %s playlist_id track_id ..." % (sys.argv[0],))
     sys.exit()
 
 scope = 'playlist-modify-public'

examples/show_user.py

@@ -1,5 +1,4 @@
-
-# shows artist info for a URN or URL
+# Shows artist info for a URN or URL
 
 from spotipy.oauth2 import SpotifyClientCredentials
 import spotipy