fixed syntax error when numpy is in path but IronPython

[chenkasirer]

Fixes #1184.

Spotted this issue on some computers where COMPAS has been installed for he first time.
Problem seems to be the presence of numpy in sys.path of IronPython. The import of numpy in encoders.py to determine if it's available raises a syntax error, probably due to python3 syntax used.

What type of change is this?

• Bug fix in a backwards-compatible manner.
• New feature in a backwards-compatible manner.
• Breaking change: bug fix or new feature that involve incompatible API changes.
• Other (e.g. doc update, configuration, etc)

Checklist

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• I added a line to the CHANGELOG.md file in the Unreleased section under the most fitting heading (e.g. Added, Changed, Removed).
• I ran all tests on my computer and it's all green (i.e. invoke test).
• I ran lint on my computer and there are no errors (i.e. invoke lint).
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• I have added tests that prove my fix is effective or that my feature works.
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[gonzalocasas]

LGTM! That actually makes a lot of sense, I didn't realize an import of py3.x might throw an exception other than ImportError

[chenkasirer]

LGTM! That actually makes a lot of sense, I didn't realize an import of py3.x might throw an exception other than ImportError

yes this seemed like such a crazy voodoo issue, but now suddenly makes a lot of sense. I find it crazy though how Ladybug add stuff to path like that..