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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 vapour_pressure(Temperature, element):
 r"""Return the vapour pressure of rubidium or cesium in Pascals. This function receives as input the temperature in Kelvins and the name of the element. 5.31769896107e-05 0.000244249795696 0.0155963687128 0.000201461144963 0.000297898928349 0.0421014384667 The element must be in the database. Traceback (most recent call last):
 ValueError: Ca is not an element in the database for this function. References: [1] Daniel A. Steck, "Cesium D Line Data," available online at http://steck.us/alkalidata (revision 2.1.4, 23 December 2010). [2] Daniel A. Steck, "Rubidium 85 D Line Data," available online at http://steck.us/alkalidata (revision 2.1.5, 19 September 2012). [3] Daniel A. Steck, "Rubidium 87 D Line Data," available online at http://steck.us/alkalidata (revision 2.1.5, 19 September 2012). """

    if element == "Rb":
        Tmelt = 39.30+273.15  # K.
        if Temperature < Tmelt:
            P = 10**(2.881+4.857-4215.0/Temperature)  # Torr.
        else:
            P = 10**(2.881+4.312-4040.0/Temperature)  # Torr.
    elif element == "Cs":
        Tmelt = 28.5 + 273.15  # K.
        if Temperature < Tmelt:
            P = 10**(2.881+4.711-3999.0/Temperature)  # Torr.
        else:
            P = 10**(2.881+4.165-3830.0/Temperature)  # Torr.
    else:
        s = str(element)
        s += " is not an element in the database for this function."
        raise ValueError(s)

    P = P * 101325.0/760.0  # Pascals.
    return P