Issue #19735: Implement private function ssl._create_stdlib_context() to
create SSLContext objects in Python's stdlib module. It provides a single
configuration point and makes use of SSLContext.load_default_certs().
diff --git a/Lib/http/client.py b/Lib/http/client.py
index 6e32c7b..5c52ba3 100644
--- a/Lib/http/client.py
+++ b/Lib/http/client.py
@@ -1179,9 +1179,7 @@
             self.key_file = key_file
             self.cert_file = cert_file
             if context is None:
-                # Some reasonable defaults
-                context = ssl.SSLContext(ssl.PROTOCOL_SSLv23)
-                context.options |= ssl.OP_NO_SSLv2
+                context = ssl._create_stdlib_context()
             will_verify = context.verify_mode != ssl.CERT_NONE
             if check_hostname is None:
                 check_hostname = will_verify