def conll_tag_chunks(chunk_sents):
	tagged_sents = [tree2conlltags(tree) for tree in chunk_sents]
	return [[(t, c) for (w, t, c) in sent] for sent in tagged_sents]
Convert each chunked sentence to list of (tag, chunk_tag) tuples,
dataset/ETHPy150Open japerk/nltk-trainer/nltk_trainer/chunking/chunkers.py/conll_tag_chunks