code: def make_format_op_generator(fmt_string):
      
      def gen(arg_types):
          converted_arg_types = list(map(get_op_format_from_const_ty, arg_types))
          op = fmt_string.format(arg_t=converted_arg_types)
          return op
      return gen
docs: Return a function which generates an op format (just a string of the vex instruction)
  
      Functions by formatting the fmt_string with the types of the arguments