code: def signed(item):
      
      if SIG in item.c_children.keys() and item.signature:
          return True
      else:
          for prop in item.c_child_order:
              child = getattr(item, prop, None)
              if isinstance(child, list):
                  for chi in child:
                      if signed(chi):
                          return True
              elif child and signed(child):
                  return True
  
      return False
docs: Is any part of the document signed ?
  
      :param item: A Samlbase instance
      :return: True if some part of it is signed