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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 match(self, selector, index):
 """Match the selector."""


        pseudo = None
        m = self.re_pseudo_name.match(selector, index)
        if m:
            name = util.lower(css_unescape(m.group('name')))
            pattern = self.patterns.get(name)
            if pattern:
                pseudo = pattern.match(selector, index)
                if pseudo:
                    self.matched_name = pattern

        return pseudo