global_stack = []

def exported_function(param):
   global global_stack
   global_stack = []
   fill_global_stack_with_possible_solutions(param)
   for sol in global_stack:
      check_solution(sol, param)
# if exported_function is called by 2 or more concurrent threads, they may interfere with each other, and there is a strong possibility that it will be called like that