Python 3.7 introduced Development Mode. The mode can be activa | Python etc
Python 3.7 introduced Development Mode. The mode can be activated with the -X dev argument and it makes the interpreter produce some helpful warnings. For instance:
+ Unclosed files. + Unawaited coroutines. + Unknown encoding for str.encode (by default, it is unchecked for empty strings). + Memory allocation issues.
$ echo 'open("/dev/null")' > tmp.py $ python3 -X dev tmp.py tmp.py:1: ResourceWarning: unclosed file <_io.TextIOWrapper name='/dev/null' mode='r' encoding='UTF-8'> open("/dev/null") ResourceWarning: Enable tracemalloc to get the object allocation traceback