如何与Python中的其他程序交互?

I want to write a Python script that runs another program, reading the output of the other program and manipulating it. The problem is that this program prompts for a password, and I cannot figure out how to supply it automatically. (For the purposes of this script, it really does not matter if the password is stored in plain-text in the script itself.) What I want to do is something like:I want to write a Python script that runs anoth