should traitlets be listed as a dependency in configuration files?

[yuluc123]

Hi I notice that traitlets are used as direct dependency in source code file-packages/python/plotly/plotly/basewidget.py . But traitlets is not listed in any configuration file. So I am wondering if traitlets should be listed in configuration files such as setup.py.

[nicolaskruchten]

To use the FigureWidget one needs to install ipywidget which depends on traitlets. ipywidgets is not a hard dependency of this library because lots of folks don't use FigureWidget :)

[yuluc123]

Thanks for your reply. But I think even traitlets is not hardcore dependency, maybe it should be introduced as an extra dependnecy for the project. Maybe it can be listed in extra requirements.txt in the sub-folders?