I got this error when running the latest 0.2.0 version (on Windows, Python 3.12.8) using:
gflabel cullenect --font=Arial "3.5x16{...}{circle(+)}"
Any easy fix for my case was to modify L452 of fragments.py to:
def _fragment_circle(height: float, _maxsize: float, *args: str) -> Sketch:
But this will obviously also affect a bunch of other functions there so I didn't create a PR (although can do if-useful)