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    "import numpy as np\n",
    "\n",
    "def tournament_selection(population, fitnesses, tournament_size=3):\n",
    "    \"\"\"\n",
    "    This function takes the entire current population, randomly selects \n",
    "    tournament_size (default=3) chromosomes from the population as candidate \n",
    "    parents and returns the candidate with the highest fitness.\n",
    "    \n",
    "    :param population: current population \n",
    "    :param fitnesses: array of fitnesses for all chromosomes in the current population.\n",
    "    :param tournament_size: number of candidate solutions to compare based on their fitness.\n",
    "    :return: chosen_parents[min_fitness_idx]: the single parent candidate with the highest fitness.\n",
    "    \"\"\"\n",
    "\n",
    "    indices_list = np.random.choice(len(population), tournament_size, replace=False)\n",
    "    \n",
    "    chosen_parents = np.array([population[i] for i in indices_list])\n",
    "\n",
    "    parent_fitnesses = np.array([fitnesses[i] for i in indices_list])\n",
    "\n",
    "    min_fitness_idx = np.argmin(parent_fitnesses)\n",
    "\n",
    "    return chosen_parents[min_fitness_idx]"
   ]
  }
 ],
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