#foobar.py
import os
import sys
try:
for i in range(5):
print i, os.ttyname(i)
except Exception as e:
print e
print sys.exc_type

$ python foobar.py

0 /dev/pts/0
1 /dev/pts/0
2 /dev/pts/0
3 [Errno 9] Bad file descriptor
<type 'exceptions.OSError'>