Haven't seen that one before. What version of Python are you using? There's some similar issues folks have asked about on StackOverflow:
If you're able to do a pip install on another machine where it does work, you could also follow the instructions in Appendix A to download the modules there, copy them over to your VizAlerts machine, and install them from your local disk rather than the Internet.
It's the latest. 2.7
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