> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/core/get-started/faq/python-undefined-symbols-error.md).

# "undefined symbol" errors when running samples

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Make sure your alias for `python` is set to `python2` if using Python 2.x or `python3` if using Python 3.x.

Additionally, the provided `runall_python.sh` script may use a different python installation than intended. Specify a python version by navigating to the sample folder (e.g. `/Samples/AddImageTest/PYTHON`) and directly running the python file (e.g. `python3 AddImageTest.py`).

Alternatively, you can use version managers such as [pyenv](https://github.com/pyenv/pyenv/) to force the samples to use the Python version of your choice.


---

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