code: def step_2_helper(word, r1, end, repl, prev):
      if word.endswith(end):
          if len(word) - len(end) >= r1:
              if prev == []:
                  return word[: -len(end)] + repl
              for p in prev:
                  if word[: -len(end)].endswith(p):
                      return word[: -len(end)] + repl
          return word
      return None
  
imports: import re
label_desc: Use image node_id 13 for calling a global function with example usage: step_2_helper(word, r1, end, repl, prev) and returns: None, word, unknown, unknown