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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 re_pipe(FlowRate, Diam, Nu):
 """Return the Reynolds Number for a pipe."""

    #Checking input validity
    ut.check_range([FlowRate, ">0", "Flow rate"], [Diam, ">0", "Diameter"],
                   [Nu, ">0", "Nu"])
    return (4 * FlowRate) / (np.pi * Diam * Nu)