import gym from rl.agents.dqn import DQNAgent from rl.memory import SequentialMemory from rl.policy import EpsGreedyQPolicy from keras.models import Sequential from keras.layers import Dense, Flatten from keras.optimizers import Adam # create environment env = gym.make('CartPole-v1') # define parameters state_size = env.observation_space.shape action_size = env.action_space.n # create Q learning model model = Sequential() model.add(Flatten(input_shape=state_size)) model.add(Dense(24, activation='relu')) model.add(Dense(24, activation='relu')) model.add(Dense(action_size, activation='linear')) # create memory memory = SequentialMemory(limit=10000, window_length=1) # create policy policy = EpsGreedyQPolicy(eps=0.1) # create DQN agent dqn_agent = DQNAgent(model=model, nb_actions=action_size, memory=memory, nb_steps_warmup=10, target_model_update=1e-2, policy=policy) # compile and fit model dqn_agent.compile(Adam(lr=1e-3), metrics=['mae']) dqn_agent.fit(env, nb_steps=5000, visualize=False, verbose=2)This example creates a DQNAgent with a neural network model consisting of two hidden layers of 24 units each with relu activation functions and a linear output layer. The agent uses an epsilon-greedy exploration policy and a replay buffer memory with a limit of 10000 samples. The model is trained for 5000 steps on the CartPole-v1 environment. Overall, the rl.agents.dqn package provides a convenient way to implement deep Q-learning agents using the DQNAgent class in Python.