def add(self, state, action, reward, next_state, done):
    'Add a new experience to memory.'
    e = self.experience(state, action, reward, next_state, done)
    self.memory.append(e)
Add a new experience to memory.
def add(self, state, action, reward, next_state, done):
    
    e = self.experience(state, action, reward, next_state, done)
    self.memory.append(e)