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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 register_library_type(name, type_):
 """ Register a Arctic Library Type handler """

    if name in LIBRARY_TYPES:
        raise ArcticException("Library %s already registered as %s" % (name, LIBRARY_TYPES[name]))
    LIBRARY_TYPES[name] = type_