allmytext = """
(CLAUSE (NP Jack/NNP) (VP loved/VBD) (NP Peter/NNP))
(CLAUSE (NP Jack/NNP) (VP stayed/VBD) (NP in/IN London/NNP))
(CLAUSE (NP Tom/NNP) (VP is/VBZ) (NP in/IN Kolkata/NNP))
"""
wrapped = '(ROOT ' + allmytext + ' )'
trees = nltk.Tree.fromstring(wrapped, read_leaf=lambda x: x.split('/')[0])
for tree in trees:
    pass
Как я могу удалить POS-теги перед косой чертой в nltk?