def instances(self, baseform=None):
        kwargs = {}
        if baseform is not None:
            kwargs['instance_filter'] = lambda inst: inst.baseform==baseform
        return StreamBackedCorpusView(self.abspath(self._nomfile),
                                      lambda stream: self._read_instance_block(stream, **kwargs),
                                      encoding=self.encoding(self._nomfile))
:return: a corpus view that acts as a list of
dataset/ETHPy150Open nltk/nltk/nltk/corpus/reader/nombank.py/NombankCorpusReader.instances