在Python中，處理依賴關系的一種方法是使用subprocess模塊來執行命令

import subprocess
import time

def run_command(command):
    process = subprocess.Popen(command, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    stdout, stderr = process.communicate()
    return process.returncode, stdout, stderr

def main():
    command1 = "echo 'Command 1 is running...'"
    command2 = "sleep 3 && echo 'Command 2 is running...'"

    # Run command1
    print(f"Running {command1}")
    exit_code1, stdout1, stderr1 = run_command(command1)
    if exit_code1 != 0:
        print(f"Error in command1: {stderr1.decode('utf-8')}")
    else:
        print(f"Success in command1: {stdout1.decode('utf-8')}")

    # Wait for command1 to finish
    time.sleep(1)

    # Run command2 with dependency on command1
    print(f"Running {command2}")
    exit_code2, stdout2, stderr2 = run_command(command2)
    if exit_code2 != 0:
        print(f"Error in command2: {stderr2.decode('utf-8')}")
    else:
        print(f"Success in command2: {stdout2.decode('utf-8')}")

if __name__ == "__main__":
    main()

在這個示例中，我們定義了一個run_command函數來執行給定的命令，并返回進程的退出代碼、標準輸出和標準錯誤。在main函數中，我們首先運行command1，然后等待1秒鐘以確保command1已完成。接下來，我們運行command2，它依賴于command1的完成。如果command2執行成功，我們將看到以下輸出：

Running Command 1 is running...
Success in command1: Command 1 is running...
Running Command 2 is running...
Success in command2: Command 2 is running...

請注意，這個示例中的依賴關系很簡單，只是等待1秒鐘。在實際應用中，你可能需要使用更復雜的方法來處理依賴關系，例如使用鎖文件、信號量或其他同步機制。