how to make a error message in python if else code example

Example 1: python try catch

try:
  # Dangerous stuff
except ValueError:
  # If you use try, at least 1 except block is mandatory!
  # Handle it somehow / ignore
except (BadThingError, HorrbileThingError) as e:
  # Hande it differently
except:
  # This will catch every exception.
else:
  # Else block is not mandatory.
  # Dangerous stuff ended with no exception
finally:
  # Finally block is not mandatory.
  # This will ALWAYS happen after the above blocks.

Example 2: except as Exception:

>>> def catch():
...     try:
...         asd()
...     except Exception as e:
...         print e.message, e.args
... 
>>> catch()
global name 'asd' is not defined ("global name 'asd' is not defined",)