def _add_exploration_noise(self, node: Node) -> None:
        """
        Overview:
            Add exploration noise.
        Arguments:
            - node (:obj:`Class Node`): Current node.
        """
        # Get a list of actions corresponding to the child nodes.
        actions = list(node.children.keys())
        # Create a list of alpha values for Dirichlet noise.
        alpha = [self._root_dirichlet_alpha] * len(actions)
        # Generate Dirichlet noise using the alpha values.
        noise = np.random.dirichlet(alpha)
        # Compute the weight of the exploration noise.
        frac = self._root_noise_weight
        # Update the prior probability of each child node with the exploration noise.
        for a, n in zip(actions, noise):
            node.children[a].prior_p = node.children[a].prior_p * (1 - frac) + n * frac

        Overview:
            Add exploration noise.
        Arguments:
            - node (:obj:`Class Node`): Current node.
        
reason/guided_search/tree.py