These symbols probably appear when the code is being copied from forum. Retyping the line where an error occured most likely will help.
File with the function and a call to it (run from GG to test, if it works): aimbot_function.lua
You don't need to do this. If it's group search and you need to search for values of different types, then you specify the type after the value. Otherwise, you don't. In your case, there is only 1 value, type of the search is "gg.TYPE_FLOAT", meaning that float value will be searched.
Example, where specifying the type is needed:
Objective — search for double value 4.32, followed by dword value 7274, followed by byte value 87 with group size equal to 14.
Search string — "4.32E; 7274D; 87B::14".