python 出错：re.error: unterminated character set at position 8

WIKI_WORD_MATCH="(([A-Z][a-z0-9){2,})"
WIKI_WORD=re.compile(WIKI_WORD_MATCH)

运行时出错：re.error: unterminated character set at position 8

查看是因为正则不正确 WIKI_WORD_MATCH="(([A-Z][a-z0-9]*){2,})"