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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_general(Vel, Area, PerimWetted, Nu):
 """Return the Reynolds Number for a general cross section."""

    #Checking input validity - inputs not checked here are checked by
    #functions this function calls.
    ut.check_range([Vel, ">=0", "Velocity"], [Nu, ">0", "Nu"])
    return 4 * radius_hydraulic_general(Area, PerimWetted).magnitude * Vel / Nu