SageMath language changes since 10.1
Terms like "var" and "pi" were usable immediately in SageMath 10.1. In SageMath 10.3, they appear to need preliminary code to work. Is there a list of such changes somewhere, at least for such basic words?
Those terms should still be available. What platform are you using and how did you install SageMath?
Also, summaries of changes from one version to the next are available at https://wiki.sagemath.org/ReleaseTours.
indeed, still there