def draw_lines(img, coords, axis, color=[255, 0, 0], lw=10):
    """Draw `color` lines on `img` at `coords` along `axis`.

    axis == 0 --> horizonal lines
    axis == 1 --> vertical lines
    line width (`lw`) will round down to even numbers.

    Raises
    ------
    IndexError
        If any (coord +/- (lw // 2)) falls outside of `img`
    """
    assert axis in [0, 1], "`axis` must be 0 (horizontal) or 1 (vertical)"

    hw = lw // 2
    if axis == 0:
        for row in coords:
            img[row - hw : row + hw + 1, :, :] = color
    else:
        for col in coords:
            img[:, col - hw : col + hw + 1, :] = color

    return img