Fields UI export to code for editing? I am creating a new registration form with the Fields UI module and need to 
be able to add variable_get instances for username, email, etc and also add
select lists for birthday info, typical drop downs like range(1,12), range(1,31), 
and range(2015,2012). I'm having trouble trying to figure out how to do this,
or how to put preset variables into my fields. Can I dump this and edit it
myself, or can I put in what I need?

EDIT

I found out that I can use list(int) then select widget type select list to create
select boxes, BUT I still cannot assign things known variables.

To further this along, lets say I have I have $variables['bio']['firstName'], I
am trying to assign name_bio_firstName to the field for name, if that doesn't confuse
anyone more.
You can export it with Features module. Basically it creates a new module which you download and plug into modules folder. There you can further edit it's code.