def get_stanford_tag(siera_tag):
    """Returns the corresponding Stanford NER tag on given Siera entity tag"""

    mapping = {
        'Individual' : lambda _: 'PERS',
        'Location' : lambda _: 'LOC',
        'Organization' : lambda _: 'ORG',
        'Brand' : lambda _: 'O',
        'Publication' : lambda _: 'O',
        'Hashtag' : lambda _: 'O'
    }

    return mapping[siera_tag](None) if siera_tag in mapping else 'O'