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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 width_rect_weir(FlowRate, Height):
 """Return the width of a rectangular weir."""

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