finding a procedure

so im trying to find a procedure, im assuming its for  block data/management, but i cannot find it, im using someones guide to make quicksand, currently remaking a 1.7.10 mod with the creators permission[?] since they've long left mod making, tho to do so, but i cannot find the yellow [__] = [__] procedure, which i need to even do this, so if anyone knows where i can find it, do tell! because im fustrated and stumped that i cannot find it anywhere!

[mod remake in question]