code: def getParent2(abfFname,groups):
      
      if ".abf" in abfFname:
          abfFname=os.path.basename(abfFname).replace(".abf","")
      for parentID in groups.keys():
          if abfFname in groups[parentID]:
              return parentID
      return abfFname
docs: given an ABF and the groups dict, return the ID of its parent.