def index(subseq, seq):
    """Return an index of `subseq`uence in the `seq`uence.
    Or `-1` if `subseq` is not a subsequence of the `seq`.
    The time complexity of the algorithm is O(n*m), where
        n, m = len(seq), len(subseq)
    >>> index([1,2], range(5))
    1
    >>> index(range(1, 6), range(5))
    -1
    >>> index(range(5), range(5))
    0
    >>> index([1,2], [0, 1, 0, 1, 2])
    3
    """
i, n, m = -1, len(seq), len(subseq)
Best Way To Determine if a Sequence is in another sequence in Python