def __init__(self, mwes=None, separator='_'):
        if not mwes:
            mwes = []
        self._mwes = Trie(mwes)
        self._separator = separator
Initialize the multi-word tokenizer with a list of expressions and a
dataset/ETHPy150Open nltk/nltk/nltk/tokenize/mwe.py/MWETokenizer.__init__