应用: 计算器
任务: 启动计算器，清空现有内容，然后输入‘120+35’
操作步骤:
step_id: 0
action: CLICK
step_id: 1
action: CLICK
step_id: 2
action: CLICK
step_id: 3
action: CLICK
step_id: 4
action: CLICK
step_id: 5
action: CLICK
step_id: 6
action: CLICK
step_id: 7
action: STOP