A shorter and less complicated version:

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import os
import re

def get_library_pathes():
    version = int(poser.Version().split(".")[0])
    fname = os.path.join(os.environ["APPDATA"],
                         "Poser" if version < 11 else "Poser Pro", str(version),
                         "LibraryPrefs.xml")
    re_libs = re.compile(r"<ContentFolder.*?folder=\"([^\"]+)\"")
    with open(fname, "r") as fh:
        for line in fh:
            res = re.search(re_libs, line)
            if res:
                yield res.group(1)


if __name__ == "__main__":
    for entry in get_library_pathes():
        print(entry)

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