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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 detect_nexson_version(blob):
 """Returns the nexml2json attribute or the default code for badgerfish"""

    n = get_nexml_el(blob)
    assert isinstance(n, dict)
    return n.get('@nexml2json', BADGER_FISH_NEXSON_VERSION)