[StackOverflow/python] How to execute command line in a python loop?

### ROOT CAUSE The user wants to execute a command line command multiple times in a loop, likely to automate repetitive tasks or process multiple inputs. The challenge is to properly handle the command execution within a loop, ensuring correct syntax and avoiding common pitfalls like forgetting to split the command or misusing subprocess modules. ### CODE FIX To execute a command line command in a Python loop, use the `subprocess.run()` function with proper argument handling. Here's a solution: ```python import subprocess # Example command (replace with your command) command = "echo 'Hello World'" for i in range(5): # Loop 5 times # Split the command into arguments (handles spaces correctly) args = command.split() # Run the command and capture output result = subprocess.run(args, capture_output=True, text=True) print(f"Output {i+1}: {result.stdout.strip()}") ``` **Key points:** 1. Use `command.split()` to split the command into arguments (avoids shell injection) 2. `capture_output=True` redirects output to Python objects 3. `text=True` ensures string output instead of bytes 4. Handle errors with `result.returncode` if needed For complex commands (with variables/escape chars), consider using `shlex.split()` or the `shell=True` parameter (with caution).