为树创建组合[Python]

class TreeNode:
    def __init__(self, value):
        self.value = value
        self.children = []

      A
    / | \
   B  C  D
  / \    \
 E   F    G

# 创建树的结构
root = TreeNode('A')
node_b = TreeNode('B')
node_c = TreeNode('C')
node_d = TreeNode('D')
node_e = TreeNode('E')
node_f = TreeNode('F')
node_g = TreeNode('G')

root.children = [node_b, node_c, node_d]
node_b.children = [node_e, node_f]
node_d.children = [node_g]

def create_combinations(root):
    if not root.children:
        return [[root.value]]
    
    combinations = []
    for child in root.children:
        child_combinations = create_combinations(child)
        for combination in child_combinations:
            combinations.append([root.value] + combination)
    
    return combinations

combinations = create_combinations(root)
for combination in combinations:
    print(combination)

['A', 'B', 'E']
['A', 'B', 'F']
['A', 'C']
['A', 'D', 'G']