code: def findentry(self, item):
          
          if not isinstance(item, str):
              raise TypeError(
                  'Members of this object must be strings. '
                  'You supplied \"%s\"' % type(item))
          for entry in self:
              if item.lower() == entry.lower():
                  return entry
          return None
docs: A caseless way of checking if an item is in the list or not.
          It returns None or the entry.