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Use "deactivate" to exit the virtualenv.  Install various packages using "pip install <packageName>" as show shown in these instructions.  Virtualenv packages can be used in batch jobs, but you must submit the job while the environment is active.

Anaconda

Unlike virtualenv, anaconda is not currently compatible with psana-python (we are actively working on this).  But it is a powerful way to install python packages outside of the psana environment.  Instructions are here.