This patch makes Python support the vendor-packages directory.
As it is Solaris-specific, it is not suitable for upstream.

--- /dev/null   2018-11-22 08:10:34.506586007 +0000
+++ Python-3.7.1/Lib/site-packages/vendor-packages.pth  2018-11-22 08:10:34.506586007 +0000
@@ -0,0 +1,1 @@
+import site; site.addsitedir('/usr/lib/python3.7/vendor-packages')