# GH python script "invalid syntax \[0:0\]" error

**URL:** <https://discourse.mcneel.com/t/gh-python-script-invalid-syntax-0-0-error/208518>\
**Category:** Grasshopper\
**Tags:** windows, python, bug, grasshopperrhino\
**Created:** [August 15, 2025, 3:06am UTC](https://discourse.mcneel.com/t/gh-python-script-invalid-syntax-0-0-error/208518 "2025-08-15T03:06:28Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![ObliqueStrategy](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/obliquestrategy/32/692280_2.png) [@ObliqueStrategy](https://discourse.mcneel.com/u/ObliqueStrategy)\
**Post date:** [August 15, 2025, 3:06am UTC](https://discourse.mcneel.com/t/gh-python-script-invalid-syntax-0-0-error/208518/1 "2025-08-15T03:06:28Z")

</div>

Hi all,

My grasshopper-based python3 script is failing with “**invalid syntax [0:0]**”

The issue looks a lot like RH-83287 [described here](https://discourse.mcneel.com/t/grasshopper-python-script-debugger-not-working/189297).

I’m running version 8 SR21 (8.21.25188.17001, 2025-07-07)

Has anyone else hit this issue?

Many thanks,

Nick.

[GH\_PythonDebugBug.gh](https://discourse.mcneel.com/uploads/short-url/AnfkvQljrnifdYZiyRxGFq7DD5c.gh) (11.6 KB)