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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 get_rotation_and_scale(header, skew_threshold=0.001):
 """Calculate rotation and CDELT."""

    ((xrot, yrot),
     (cdelt1, cdelt2)) = get_xy_rotation_and_scale(header)

    if math.fabs(xrot) - math.fabs(yrot) > skew_threshold:
        raise ValueError("Skew detected: xrot=%.4f yrot=%.4f" % (
            xrot, yrot))
    rot = yrot

    lonpole = float(header.get('LONPOLE', 180.0))
    if lonpole != 180.0:
        rot += 180.0 - lonpole

    return (rot, cdelt1, cdelt2)