[cleanup] linter, code formatting and readme

ytdlp_plugins/extractor/__init__.py

@@ -1,2 +1,3 @@
 # flake8: noqa
+
 from .sample import SamplePluginIE

ytdlp_plugins/extractor/sample.py

@@ -1,11 +1,13 @@
+# coding: utf-8
+
 from __future__ import unicode_literals
 
-# Don't use relative imports
+# ⚠ Don't use relative imports
 from yt_dlp.extractor.common import InfoExtractor
 
 
-# See https://github.com/ytdl-org/youtube-dl#adding-support-for-a-new-site
-# for instuctions on making extractors
+# ℹ️ Instructions on making extractors can be found at:
+# 🔗 https://github.com/ytdl-org/youtube-dl#adding-support-for-a-new-site
 
 class SamplePluginIE(InfoExtractor):
     _WORKING = False