Python
Python-specific execution probe
When an input appears to be evaluated as a Python expression, a harmless call to str() can help confirm that the result is being executed rather than reflected verbatim. Adapt the surrounding quotes to the injection context:[1]
"+str(True)+" # If True is printed, the expression was evaluated.Do not treat this probe alone as proof that arbitrary statements or operating-system commands can run; the sink may expose only a restricted expression language.