How do I set the driver's python version in spark?
I had the same problem, just forgot to activate my virtual environment.
I'm using spark 1.4.0-rc2 so I can use python 3 with spark.  If I add export PYSPARK_PYTHON=python3 to my .bashrc file, I can run spark interactively with python 3.  However, if I want to run a standalone program in local mode, I get an error:

Exception: Python in worker has different version 3.4 than that in
driver 2.7, PySpark cannot run with different minor versions

How can I specify the version of python for the driver?  Setting export PYSPARK_DRIVER_PYTHON=python3 didn't work.