import unicodedata


def to_ascii(s):
    """https://github.com/scikit-learn/scikit-learn/blob/adc1e590d4dc1e230b49a4c10b4cd7b672bb3d69/sklearn/feature_extraction/text.py#L70"""
    nkfd_form = unicodedata.normalize('NFKD', s)
    return nkfd_form.encode('ASCII', 'ignore').decode('ASCII')