code: def mutate_random_individual(population, toolbox):
      
      idx = np.random.randint(0,len(population))
      ind = population[idx]
      ind, = toolbox.mutate(ind)
      del ind.fitness.values
      return ind
docs: Picks a random individual from the population, and performs mutation on a copy of it.
  
      Parameters
      ----------
      population: array of individuals
  
      Returns
      ----------
      individual: individual
          An individual which is a mutated copy of one of the individuals in population,
          the returned individual does not have fitness.values