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**Expected behavior:**


**Actual behavior:**


**Steps to reproduce**

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- **Operating System**: <!-- e.g. Windows XP / Ubuntu 16.04 / Mac OS 10.5 -->
- **Vim Version**: <!-- first two lines of `:version` output -->
- **UltiSnips Version**: <!-- e.g. 3.1. If you're using version from git 
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- **Python inside Vim**: <!-- e.g. 2.7.14 / 3.6.5. If unsure run inside vim:
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                              `:py3 import sys; print(sys.version)' -->
- **Docker repo/vimrc**: <!-- link to the branch containing the repro case, 
                              or the uploaded minimal vimrc -->