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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 convtable2dict(convtable, locale, update=None):
 """ Convert a list of conversion dict to a dict for a certain locale. [('列斯', '利兹'), ('利兹', '利兹'), ('巨集', '宏'), ('里茲', '利兹')] """

    rdict = update.copy() if update else {}
    for r in convtable:
        if ':uni' in r:
            if locale in r:
                rdict[r[':uni']] = r[locale]
        elif locale[:-1] == 'zh-han':
            if locale in r:
                for word in r.values():
                    rdict[word] = r[locale]
        else:
            v = fallback(locale, r)
            for word in r.values():
                rdict[word] = v
    return rdict