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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 reign_year_to_ad(reign_year: int, reign: int) -> int: """ Reign year of Chakri dynasty, Thailand """

    if int(reign) == 10:
        ad = int(reign_year) + 2015
    elif int(reign) == 9:
        ad = int(reign_year) + 1945
    elif int(reign) == 8:
        ad = int(reign_year) + 1928
    elif int(reign) == 7:
        ad = int(reign_year) + 1924
    return ad