def METHOD_NAME(self, corpus: Corpus,
                                 callback: Callable) -> Corpus:
    """
    Create tokens from documents and set corpus.tokens.
    :param corpus: Corpus
    :param callback: progress callback function
    :return: Corpus
        Preprocessed corpus.
    """
    assert callback is not None
    tokens, n = [], len(corpus.pp_documents)
    for i, doc in enumerate(corpus.pp_documents):
        callback(i / n)
        tokens.append(self._preprocess(doc))
    corpus.pos_tags = None
    corpus.store_tokens(tokens)
    return corpus