Override python version with value from cmdline

install/from-scratch.sh

@@ -23,6 +23,6 @@ if [ -d ${BASEDIR}/envs/${NAME} ]; then
 fi
 
 echo "[>>] Creating environment ${NAME} for python ${PYTHON_VERSION} with bob dependencies..."
-${CONDA} env create -n ${NAME} --file=bob-devel.yml
+${CONDA} env create -n ${NAME} --file=bob-devel.yml python=${PYTHON_VERSION}
 echo "[>>] Bye!"
 exit 0