<s>[INST] Calling an external command in Python How can I call an external command (as if I'd typed it at the Unix shell or Windows command prompt) from within a Python script?
 [/INST] Look at the subprocess module in the stdlib:
from subprocess import call
call(["ls", "-l"])

The advantage of subprocess vs system is that it is more flexible (you can get the stdout, stderr, the "real" status code, better error handling, etc...). I think os.system is deprecated, too, or will be:
https://docs.python.org/2/library/subprocess.html#replacing-older-functions-with-the-subprocess-module
For quick/dirty/one time scripts, os.system is enough, though.
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