def index(self, element):
        for i, child in enumerate(self.contents):
            if child is element:
                return i
        raise ValueError("Tag.index: element not in tag")
Return counts of words of length `k` from this sequence.
dataset/ETHPy150Open socketubs/pyhn/pyhn/lib/bs4_py3/element.py/Tag.index--crossover with--dataset/ETHPy150Open biocore/scikit-bio/skbio/sequence/_sequence.py/Sequence.kmer_frequencies