add new block for fstring

[hloi]

Hello, how would I go about to add a new fstring block for the print function. Right now I add a new checkbox to the List and convert it to a fstring format when the checkbox is checked.
It works fine in this approach except that I won't able to reload the code back to the Blockly canvas for the list.
Also, when I create a new Block such as fstring, I don't know how to add it to BlockMirror. I add f" or fstring(___) in the toolbox.js but I don't know how to tie it to ast_fstring.js to customize the fstring function.
Any suggestion would be greatly appreciated.

[hloi]

Hello, I'm attempting to add the following expression: print(f'this is a test num') using fstring for the print command. I attempted to edit toolbars.js, but it did not work. Any assistance would be greatly appreciated!