code: def findspans(self, type,set=None):
          
          if issubclass(type, AbstractAnnotationLayer):
              layerclass = type
          else:
              layerclass = ANNOTATIONTYPE2LAYERCLASS[type.ANNOTATIONTYPE]
          e = self
          while True:
              if not e.parent: break
              e = e.parent
              for layer in e.select(layerclass,set,False):
                  for e2 in layer:
                      if isinstance(e2, AbstractSpanAnnotation):
                          if self in e2.wrefs():
                              yield e2
docs: Find span annotation of the specified type that include this word