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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 _OsmoticPressure(T, P, S):
 """Procedure to calculate the osmotic pressure of seawater Parameters T : float Tmperature, [K] P : float Pressure, [MPa] S : float Salinity, [kg/kg] Returns ------- Posm : float Osmotic pressure, [MPa] References IAPWS, Advisory Note No. 5: Industrial Calculation of the Thermodynamic Properties of Seawater, http://www.iapws.org/relguide/Advise5.html, Eq 15 """

    pw = _Region1(T, P)
    gw = pw["h"]-T*pw["s"]

    def f(Posm):
        pw2 = _Region1(T, P+Posm)
        gw2 = pw2["h"]-T*pw2["s"]
        ps = SeaWater._saline(T, P+Posm, S)
        return -ps["g"]+S*ps["gs"]-gw+gw2

    Posm = fsolve(f, 0)[0]
    return Posm