except errors python code example

Example 1: catch error python

import traceback

dict = {'a':3,'b':5,'c':8}
try:
  print(dict[q])
 
except:
  traceback.print_exc()
  
# This will trace you back to the line where everything went wrong. 
# So in this case you will get back line 5

Example 2: python catch exception

try:
   # Code to test / execute
   print('Test')
except (SyntaxError, IndexError) as E:  # specific exceptions
   # Code in case of SyntaxError for example
   print('Synthax or index error !')
except :
   # Code for any other exception
   print('Other error !')
else:
   # Code if no exception caught
   print('No error')
finally:
   # Code executed after try block (success) or any exception (ie everytime)
   print('Done')

# This code is out of try / catch bloc
print('Anything else')

Example 3: python 3 except sys error info

1 import sys
   2 try:
   3   untrusted.execute()
   4 except: # catch *all* exceptions
   5   e = sys.exc_info()[0]
   6   write_to_page( "<p>Error: %s</p>" % e )