Plugin cleanup and tweaks

plugins/youtube_download/yt_dlp/postprocessor/exec.py

@@ -1,14 +1,8 @@
-from __future__ import unicode_literals
-
 import subprocess
 
 from .common import PostProcessor
 from ..compat import compat_shlex_quote
-from ..utils import (
-    encodeArgument,
-    PostProcessingError,
-    variadic,
-)
+from ..utils import PostProcessingError, encodeArgument, variadic
 
 
 class ExecPP(PostProcessor):