improve render_vis docstring

[marlonjan]

No description provided.

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[marlonjan]

Signed the CLA 👍

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[coveralls]

Pull Request Test Coverage Report for Build 546

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 70.492%

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Totals
Change from base Build 535:	0.0%
Covered Lines:	1763
Relevant Lines:	2501

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💛 - Coveralls

[ludwigschubert]

Thanks, @marlonjan !