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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 replace(self, v):
 """Replace an individual selected by negative tournament selection with individual v"""

        if self.popsize < self._popsize:
            return self.add(v)
        k = self.tournament(negative=True)
        self.clean(self.population[k])
        self.population[k] = v
        v.position = len(self._hist)
        self._hist.append(v)
        self.bsf = v
        self.estopping = v
        self._inds_replace += 1
        self._density += self.get_density(v)
        if self._inds_replace == self._popsize:
            self._inds_replace = 0
            self.generation += 1
            gc.collect()