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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_TP(T, P):
 """Region definition for input T and P Parameters T : float Temperature, [K] P : float Pressure, [MPa] 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. 2.3 """

    region = None
    if 1073.15 < T <= 2273.15 and Pmin <= P <= 50:
        region = 5
    elif Pmin <= P <= Ps_623:
        Tsat = _TSat_P(P)
        if 273.15 <= T <= Tsat:
            region = 1
        elif Tsat < T <= 1073.15:
            region = 2
    elif Ps_623 < P <= 100:
        T_b23 = _t_P(P)
        if 273.15 <= T <= 623.15:
            region = 1
        elif 623.15 < T < T_b23:
            region = 3
        elif T_b23 <= T <= 1073.15:
            region = 2
    return region