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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 flow_rect_weir(Height, Width):
 """Return the flow of a rectangular weir."""

    #Checking input validity
    ut.check_range([Height, ">0", "Height"], [Width, ">0", "Width"])
    return ((2/3) * con.VC_ORIFICE_RATIO
            * (np.sqrt(2*gravity.magnitude) * Height**(3/2))
            * Width)