def METHOD_NAME(self, stream, tagset=None):
    # returns at most 1 discourse.  (The other methods depend on this.)
    return [
        [
            self._parse_utterance(u, include_tag=True, tagset=tagset)
            for b in read_blankline_block(stream)
            for u in b.split("\n")
            if u.strip()
        ]
    ]