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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 update_q(self, state_key, action_key, reward_value, next_max_q):
        '''
        Update Q-Value.

        Args:
            state_key:              The key of state.
            action_key:             The key of action.
            reward_value:           R-Value(Reward).
            next_max_q:             Maximum Q-Value.

        '''
        # Now Q-Value.
        q = self.extract_q_df(state_key, action_key)
        # Update Q-Value.
        new_q = q + self.alpha_value * (reward_value + (self.gamma_value * next_max_q) - q)
        # Save updated Q-Value.
        self.save_q_df(state_key, action_key, new_q)