How to embed only one cell?

I can’t find in the documentation how to do this.
I want to embed only one cell of the notebook to keep the visible code clean. I noticed rambda docs - have it set up that way with importing the package in a different cell while still having access to the variables in the visible code.
How can I achieve the same effect?

Hi there,

Check out the preamble field in the Embeds documentation here:

- Randy