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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 _adjust_probability_vec_best(population, fitnesses, probability_vec, adjust_rate):
 """Shift probabilities towards the best solution."""

    best_solution = max(zip(fitnesses, population))[1]

    # Shift probabilities towards best solution
    return _adjust(probability_vec, best_solution, adjust_rate)