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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 iter_platform_files(dst):
 """ Walk a directory and yield each full path that is a Mach-O file """
 
    for root, dirs, files in os.walk(dst):
        for fn in files:
            fn = os.path.join(root, fn)
            if is_platform_file(fn):
                yield fn