def update(self, docs=None, split=<NUM_LIT:0>, parallelism=None, progress_bar=True):
self.apply(<EOL>docs=docs,<EOL>split=split,<EOL>train=True,<EOL>clear=False,<EOL>parallelism=parallelism,<EOL>progress_bar=progress_bar,<EOL>)<EOL>
Update the features of the specified candidates.

        :param docs: If provided, apply features to all the candidates in these
            documents.
        :param split: If docs is None, apply features to the candidates in this
            particular split.
        :type split: int
        :param parallelism: How many threads to use for extraction. This will
            override the parallelism value used to initialize the Featurizer if
            it is provided.
        :type parallelism: int
        :param progress_bar: Whether or not to display a progress bar. The
            progress bar is measured per document.
        :type progress_bar: bool