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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 duplicate(self):
 """Duplicates the matcher to others."""

        other = Matcher(self.loc, self.check_var, self.checkdefs, self.names, self.var_index)
        other.insert_check(0, "not " + self.check_var)
        self.others.append(other)
        return other