def calc_anchor_heights(k: int = 10, fixed_width: int = 16):
    """
    Anchor heights:
    1. fixed_width / 0.7 ** -1, i.e. 70% fixed_width
    2. fixed_width / 0.7 ** 0， i.e. fixed_width
    3. fixed_width / 0.7 ** 1
    4. fixed_width / 0.7 ** 2
    ...
    10. fixed_width / 0.7 ** 8
    """
    r = 0.7
    s = -1
    return [round(fixed_width / r ** e) for e in range(s, k + s)]