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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 _Bound_Ph(P, h):
 """Region definition for input P y h Parameters P : float Pressure, [MPa] h : float Specific enthalpy, [kJ/kg] Returns ------- region : float IAPWS-97 region code References Wagner, W; Kretzschmar, H-J: International Steam Tables: Properties of Water and Steam Based on the Industrial Formulation IAPWS-IF97; Springer, 2008; doi: 10.1007/978-3-540-74234-0. Fig. 2.5 """

    region = None
    if Pmin <= P <= Ps_623:
        h14 = _Region1(_TSat_P(P), P)["h"]
        h24 = _Region2(_TSat_P(P), P)["h"]
        h25 = _Region2(1073.15, P)["h"]
        hmin = _Region1(273.15, P)["h"]
        hmax = _Region5(2273.15, P)["h"]
        if hmin <= h <= h14:
            region = 1
        elif h14 < h < h24:
            region = 4
        elif h24 <= h <= h25:
            region = 2
        elif h25 < h <= hmax:
            region = 5
    elif Ps_623 < P < Pc:
        hmin = _Region1(273.15, P)["h"]
        h13 = _Region1(623.15, P)["h"]
        h32 = _Region2(_t_P(P), P)["h"]
        h25 = _Region2(1073.15, P)["h"]
        hmax = _Region5(2273.15, P)["h"]
        if hmin <= h <= h13:
            region = 1
        elif h13 < h < h32:
            try:
                p34 = _PSat_h(h)
            except NotImplementedError:
                p34 = Pc
            if P < p34:
                region = 4
            else:
                region = 3
        elif h32 <= h <= h25:
            region = 2
        elif h25 < h <= hmax:
            region = 5
    elif Pc <= P <= 100:
        hmin = _Region1(273.15, P)["h"]
        h13 = _Region1(623.15, P)["h"]
        h32 = _Region2(_t_P(P), P)["h"]
        h25 = _Region2(1073.15, P)["h"]
        hmax = _Region5(2273.15, P)["h"]
        if hmin <= h <= h13:
            region = 1
        elif h13 < h < h32:
            region = 3
        elif h32 <= h <= h25:
            region = 2
        elif P <= 50 and h25 <= h <= hmax:
            region = 5
    return region