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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 get_program_files_dir():
 """ returns the location of the "program files" directory on a windows platform """

    ProgramFiles = bjam.variable("ProgramFiles")
    if ProgramFiles:
        ProgramFiles = ' '.join(ProgramFiles)
    else:
        ProgramFiles = "c:\\Program Files"
    return ProgramFiles