<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def setupuv(rc):
 """ Horn Schunck legacy OpenCV function requires we use these old-fashioned cv matrices, not numpy array """

    if cv is not None:
        (r, c) = rc
        u = cv.CreateMat(r, c, cv.CV_32FC1)
        v = cv.CreateMat(r, c, cv.CV_32FC1)
        return (u, v)
    else:
        return [None]*2