How to know if python script was run using interpreter's -m option?

Question

I couldn\'t find answer after having read all the following:

• PEP 338 Executing modules as scripts
• documentation of runpy standard modul

Answer 1

Another observation is that __package__ is set to None when executing the script directly and to the package name when using -m (using the empty string when the module isn't included in any package, so it's still different from None).