[Python] Calculator formulae

When we say Formulae, are we talking about user level expressions or built-in functions? For example, is it gradient(foo) / mag(gradient(foo)) or is it just gradient()? I assumed it was the first. I was suggesting a drop-down menu for the second also.

User defined expression. gradient(foo) / mag(gradient(foo))

The calculator already have built-in methods that the user can click on.
The python calculator do not have that but rely on the python/numpy knowledge of the user.
We do not plan to improve this in this context.