Fix broken link to Certifi
@@ -15,7 +15,7 @@ Certifi CA Bundle
validating the trustworthiness of SSL certificates while verifying the
identity of TLS hosts. It has been extracted from the Requests project.
-.. _Certifi: http://certifi.io/en/latest/
+.. _Certifi: https://github.com/certifi/python-certifi
CacheControl
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