code: def alternatives(self, Class=None, set=None):
          
  
          for e in self.select(AlternativeLayers,None, True, ['Original','Suggestion']): #pylint: disable=too-many-nested-blocks
              if Class is None:
                  yield e
              elif len(e) >= 1: #child elements?
                  for e2 in e:
                      try:
                          if isinstance(e2, Class):
                              try:
                                  if set is None or e2.set == set:
                                      yield e #not e2
                                      break #yield an alternative only once (in case there are multiple matches)
                              except AttributeError:
                                  continue
                      except AttributeError:
                          continue
docs: Generator over alternatives, either all or only of a specific annotation type, and possibly restrained also by set.
  
          Arguments:
              * ``Class`` - The Class you want to retrieve (e.g. PosAnnotation). Or set to None to select all alternatives regardless of what type they are.
              * ``set``   - The set you want to retrieve (defaults to None, which selects irregardless of set)
  
          Returns:
              Generator over Alternative elements