Adding code documentation

[petergthatsme]

We would like to add more complete documentation to the scqubits source code.

Here we ask for documenting signatures of 15 items such methods, functions, classes, etc, where the details are either incomplete, or missing completely.
Documentation should follow standards observed by the rest of the code.

Alternatively, fixing type annotation shown by rynning mypy . in the main folder would also qualify towards this goal.

[WingCode]

@petergthatsme I would like to take a stab at this issue. Could you assign it to me?

[Algh89110377]

Hi Peter, I can also add documentation to the codes. Will you please add me?

[MihirsinhChauhan]

hey I'm interested ,
can you assign me this

[nathanshammah]

Just to clarify the rules of unitaryHACK (https://unitaryhack.dev/project-guide/): anyone is welcome to work on open issues, until they are closed. Issues do not need to be assigned to volunteers by maintainers before a pull request is approved (they can, but it's not required, and should not discourage other folks from participating). Thanks all for your interest!

[natestemen]

Congrats @WingCode for the successful hack! @petergthatsme Nice work with the actionable bounty as well.

Please ensure @WingCode is the only assignee to this issue so our systems know he should be rewarded.