def count_stair_ways(n):
    """Count the numbers of ways to walk up a flight of stairs with 'n' steps while taking a maximum of 2 steps at a time
    >>> count_stair_ways(2)
    2
    >>> count_stair_ways(3)
    3
    >>> count_stair_ways(4)
    5
    >>> count_stair_ways(5)
    8
    """
    """BEGIN PROBLEM 3.1"""
    # Hint: This is actually a slight modification of the recursive fibonacci
    # function, in that the input to output mapping is off by 1 spot
    # i.e. instead of: (2, 3, 4, 5) => (1, 2, 3, 5)
    #     we get this: (2, 3, 4, 5) => (2, 3, 5, 8)
    if n < 0:
        return 0
    elif n == 0:
        return 1
    else:
        return count_stair_ways(n - 1) + count_stair_ways(n - 2)
    """END PROBLEM 3.1"""