Update setup.py

Author: Anselmoo

setup.py

@@ -63,7 +63,7 @@ def requirments():
         "License :: OSI Approved :: MIT License",
         "Operating System :: MacOS",
         "Operating System :: Unix",
-        "Operating System :: Windows",
+        "Operating System :: Microsoft :: Windows",
         "Programming Language :: Python :: 3",
         "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: 3.7",