Modifies the internal state based a change to the content and returns
        the sets of words added and removed.

        :Parameters:
            checksum : `hashable`
                A checksum generated from the text of a revision
            opdocs : `iterable` ( `dict` )
                A sequence of operations that represent the diff of this new
                revision
            revision : `mixed`
                Revision metadata

        :Returns:
            A triple of lists:

            current_tokens : `list` ( :class:`~mwpersistence.Token` )
                A sequence of Tokens representing the revision that was just
                processed.
            tokens_added : `list` ( :class:`~mwpersistence.Token` )
                Tokens that were added while updating state.
            tokens_removed : `list` ( :class:`~mwpersistence.Token` )
                Tokens that were removed while updating state.

def update_opdocs(self, checksum, opdocs, revision=None):
        """
        Modifies the internal state based a change to the content and returns
        the sets of words added and removed.

        :Parameters:
            checksum : `hashable`
                A checksum generated from the text of a revision
            opdocs : `iterable` ( `dict` )
                A sequence of operations that represent the diff of this new
                revision
            revision : `mixed`
                Revision metadata

        :Returns:
            A triple of lists:

            current_tokens : `list` ( :class:`~mwpersistence.Token` )
                A sequence of Tokens representing the revision that was just
                processed.
            tokens_added : `list` ( :class:`~mwpersistence.Token` )
                Tokens that were added while updating state.
            tokens_removed : `list` ( :class:`~mwpersistence.Token` )
                Tokens that were removed while updating state.
        """
        return self._update(checksum=checksum, opdocs=opdocs,
                            revision=revision)