def METHOD_NAME(self, first, second):
    if self.are_ignored(first, second):
        return
    try:
        matches = self._ignored[first]
        matches.add(second)
    except KeyError:
        try:
            matches = self._ignored[second]
            matches.add(first)
        except KeyError:
            matches = set()
            matches.add(second)
            self._ignored[first] = matches
    self._count += 1