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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 _normalize_label(self, s, wsmap):
 """ normalized form of a synonym """

        toks = []
        for tok in list(set(self.npattern.sub(' ', s).split(' '))):
            if tok in wsmap:
                tok=wsmap[tok]
            if tok != "":
                toks.append(tok)
        toks.sort()
        return " ".join(toks)