Python is a high-level, multi-paradigm programming language that is both easy to learn and useful in a wide variety of applications. Python has a large standard library as well as a large number of third-party extensions, most of which are completely free and open source.
Availability and Restrictions
Versions
Python is available on Pitzer and Owens Clusters. The versions currently available at OSC are:
Version | Owens | Pitzer | Ascend | Notes |
---|---|---|---|---|
2.7 | X | |||
3.5 | X | |||
3.6 | X | |||
2.7-conda5.2 | X | X | Anaconda 5.2 distribution with Python 2.7 (conda 4.5.9 on Owens, conda 4.5.10 on Pitzer)** | |
3.6-conda5.2 | X* | X* | Anaconda 5.2 distribution with Python 3.6 (conda 4.5.9 on Owens, conda 4.5.11 on Pitzer)** | |
3.7-2019.10 |
X | X | Anaconda 2019.10 distribution with Python 3.7 (conda 4.7.12)** | |
3.9-2022.05 | X | X | Anaconda 2022.05 distribution with Python 3.9 (conda 4.12.0)** | |
3.9 | X* |
Some versions installed as an integrated package Anaconda.
You can use module spider python
to view available modules for a given machine. Feel free to contact OSC Help if you need other versions for your work.
Access
Python is available for use by all OSC users.
Publisher/Vendor/Repository and License Type
Python Software Foundation, Open source
Usage
Terminal
Set-up
To load the default version of Python module, use module load python
. To select a particular software version, use module load python/version
. For example, use module load python/3.5
to load Python version 3.5. After the module is loaded, you can run the interpreter by using the command python
. To unload the Python 3.5 module, use the command module unload python/3.5
or simply module unload python
.
Installed Modules
We have installed a number of Python packages and tuned them for optimal performance on our systems. When using the Anaconda distributions of python you can run conda list
to view the installed packages.
- Due to architecture differences between our supercomputers, we recommend NOT installing your own packages in
~/.local
. Instead, you should install them in some other directory and set$PYTHONPATH
in your default environment. For more information about installing your own Python modules, please see our HOWTO.
Environments
See the HOWTO section for more information on how to create and use python environements.
Batch
When you log into owens.osc.edu or pitzer.osc.edu you are actually logged into a linux box referred to as the login node. To gain access to the mutiple processors in the computing environment, you must submit your job to the batch system for execution. Batch jobs can request mutiple nodes/cores and compute time up to the limits of the OSC systems. Refer to Queues and Reservations and Batch Limit Rules for more info.
Here is an example batch job script
#!/bin/bash #SBATCH --account <your_project_id> #SBATCH --job-name Python_ExampleJob #SBATCH --nodes=1 #SBATCH --time=00:01:00 module load python/3.9-2022.05 cp example.py $TMPDIR cd $TMPDIR python example.py cp -p * $SLURM_SUBMIT_DIR
Jupyter
Launching Jupyter App
Log on to https://ondemand.osc.edu/ with your OSC credentials. Choose Jupyter under the InteractiveApps option.
Provide job submission parameters then click Launch.

The next page shows the status of your job either as Queued or Starting or Running. Your job may sit in a queue for a few minutes depending on cluster load and resources requested.

When the job is ready, please click on Connect to Jupyter. This will now launch a Jupyter App.

Jupyter App Usage
With the app open, you will be able to access your home directory on the left and all your available kernels will appear on the right. Any custom kernels created using HOWTO: create virtual environment with jupyter will also appear in this selection.
With a file open you can easily switch between different kernels by clicking the kernel name in the top right.
HOW-TOs
Manage your Python packages
We highly recommend creating a local environment to manage Python packages for your production and research tasks. Please refer to the following how-to pages for more details:
- Create a Local Python Environment
- Install Python Packages from source
- Use Local Python Environment with Jupyter
Install packages for deep/machine learning
Advanced topics
- Use GPU for Python
- Run Python in Parallel
- Python for Classroom (Intended for PI accounts, not for general users)
Known Issues
Incorrect MPI launcher and compiler wrappers with Conda environments
Versions Affected: Python 2.7, 3.6 & Conda 5.2
python/2.7-conda5.2
and python/3.6-conda5.2
. If users experience these issues, please re-load MPI module, e.g. module load mvapich2
after setting up your Conda environment.Further reading
Extensive documentation of the Python programming language and software downloads can be found at the Official Python Website.