traceback.print_exc（）python问题

Question

I am using the following line of code in IDLE to print out my traceback in an eception:

traceback.print_exc()

For some reason I get the red text error message, but then it is followed by a blue text of "None".

Not sure what that None is about, any ideas?

Answer 1

print_exc() prints formatted exception to stderr. If you need string value, call format_exc()

Answer 2

print_exc() doesn't return anything, which in Python is actually returning None . Looks like IDLE is showing you the None it returned.