update fabfile

fabfile.py

@@ -77,6 +77,12 @@ def buildVenv():
         with prefix("source ~/tbookbuild/venv/bin/activate"):
             run("pip3 install -r requirements.txt")
 
+@task
+def buildTwoVenv():
+    local("virtualenv -p $(which python2) ./venv")
+    with prefix("source ./venv/bin/activate"):
+        local("pip2 install -r ./requirements.txt")
+
 @task
 def buildLocalVenv():
     with lcd("~/TextbookEngine/build"):