如何用python在docplex中设置一个四维变量？

from docplex.mp.model import Model

model = Model(name='四维变量示例')

x = model.continuous_var_list(keys1, keys2, keys3, keys4, lb=0, ub=10, name='x')

model.add_constraint(x[1, 2, 3, 4] + x[5, 6, 7, 8] <= 10, '约束条件1')

model.maximize(x[1, 2, 3, 4] + x[5, 6, 7, 8])

model.solve()

from docplex.mp.model import Model

# 创建模型对象
model = Model(name='四维变量示例')

# 定义四维变量
keys1 = [1, 2, 3]
keys2 = [4, 5, 6]
keys3 = [7, 8, 9]
keys4 = [10, 11, 12]
x = model.continuous_var_list(keys1, keys2, keys3, keys4, lb=0, ub=10, name='x')

# 设置约束条件
model.add_constraint(x[1, 2, 3, 4] + x[5, 6, 7, 8] <= 10, '约束条件1')

# 设置目标函数
model.maximize(x[1, 2, 3, 4] + x[5, 6, 7, 8])

# 求解模型
model.solve()

# 输出结果
print('目标函数值：', model.objective_value)
print('四维变量x的取值：', x.solution_value)