Update the lassen config site file for 3.1.
#/usr/workspace/wsa/visit/visit/thirdparty_shared/3.1.0/blueos/cmake/3.9.3/linux-ppc64le_gcc-4.9/bin/cmake
##
## ./build_visit3_1_0 generated host.cmake
-## created: Thu Nov 14 13:59:40 PST 2019
+## created: Tue Dec 10 11:44:44 PST 2019
## system: Linux lassen709 4.14.0-115.10.1.1chaos.ch6a.ppc64le #1 SMP Thu Aug 8 15:51:58 PDT 2019 ppc64le ppc64le ppc64le GNU/Linux
## by: brugger
@@ -69,6 +69,7 @@ VISIT_OPTION_DEFAULT(VISIT_OPENSSL_DIR ${VISITHOME}/openssl/1.0.2j/${VISITARCH})
## Python
##
VISIT_OPTION_DEFAULT(VISIT_PYTHON_DIR ${VISITHOME}/python/2.7.14/${VISITARCH})
+VISIT_OPTION_DEFAULT(VISIT_PYTHON3_DIR ${VISITHOME}/python/3.7.5/${VISITARCH})
##
## LLVM
