code: def _negateCategory(a):
      if a == "h":
          return "v"
      if a == "v":
          return "h"
      assert a in "0r"
      return a
  
imports: from fontTools.cffLib import maxStackLimit
label_desc: Use image node_id 12 for calling a global function with example usage: _negateCategory(a) and returns: a, str, str