Successful on mac, almost there on ubuntu

requirements/system/ubuntu/apt-packages.txt

+ruby-rvm
+curl
 python-software-properties
 pkg-config
-curl
 git
 python-virtualenv
+virtualenvwraper
 build-essential
 python-dev
 gfortran

scripts/create-dev-env.sh

@@ -380,7 +380,15 @@ export WORKON_HOME=$PYTHON_DIR
 
 # Load in the mkvirtualenv function if needed
 if [[ `type -t mkvirtualenv` != "function" ]]; then
-  source `which virtualenvwrapper.sh`
+    case `uname -s` in
+        Darwin)
+            source `which virtualenvwrapper.sh`
+        ;;
+
+        *)
+            source /etc/bash_completion.d/virtualenvwrapper
+        ;;
+    esac
 fi
 
 # Create edX virtualenv and link it to repo