backport many ssl features from Python 3 (closes #21308)

A contribution of Alex Gaynor and David Reid with the generous support of
Rackspace. May God have mercy on their souls.
diff --git a/Lib/test/capath/4e1295a3.0 b/Lib/test/capath/4e1295a3.0
new file mode 100644
index 0000000..9d7ac23
--- /dev/null
+++ b/Lib/test/capath/4e1295a3.0
@@ -0,0 +1,14 @@
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