also specify the base url in metadata

Author: akhmerov

setup.py

@@ -14,6 +14,7 @@
     author = 'Jupyter Development Team',
     author_email = '[email protected]',
     description = 'Jupyter Sphinx Extensions',
+    url = 'https://github.com/jupyter/jupyter-sphinx/',
     project_urls = {
         'Bug Tracker': 'https://github.com/jupyter/jupyter-sphinx/issues/',
         'Documentation': 'https://jupyter-sphinx.readthedocs.io',