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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def keypoint_vflip(kp, rows, cols):
 """Flip a keypoint vertically around the x-axis."""

    x, y, angle, scale = kp
    c = math.cos(angle)
    s = math.sin(angle)
    angle = math.atan2(-s, c)
    return [x, (rows - 1) - y, angle, scale]