def get_ens(sets):
    """
    Puts all entities appeared in interpretation sets in one set.

    :param sets: [{en1, en2, ...}, {en3, ..}, ...]
    :return: set {en1, en2, en3, ...}
    """
    ens = set()
    for en_set in sets:
        for en in en_set:
            ens.add(en)
    return ens