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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 head_orifice(Diam, RatioVCOrifice, FlowRate):
 """Return the head of the orifice."""

    #Checking input validity
    ut.check_range([Diam, ">0", "Diameter"], [FlowRate, ">0", "Flow rate"],
                   [RatioVCOrifice, "0-1", "VC orifice ratio"])
    return ((FlowRate
             / (RatioVCOrifice * area_circle(Diam).magnitude)
             )**2
            / (2*gravity.magnitude)
            )