def pairs(a):
    """Return array of pairs of adjacent elements in a.

    >>> pairs([1, 2, 3, 4])
    array([[1, 2],
           [2, 3],
           [3, 4]])

    """
    a = np.asarray(a)
    return as_strided(a, shape=(a.size - 1, 2), strides=a.strides * 2)
Return array of pairs of adjacent elements in a.

    >>> pairs([1, 2, 3, 4])
    array([[1, 2],
           [2, 3],
           [3, 4]])