Core Python Programming (2nd Edition)

except Exception, e:
# handle real errors
If you really want to catch all errors, you can still do that too, but use BaseException instead:
try:
:
except BaseException, e:
# handle all errors
And of course, there is the less preferred bare except.
Core Style: Do not handle and ignore all errors
The try-except statement has been included in Python to provide a
powerful mechanism for programmers to track down potential errors
and perhaps to provide logic within the code to handle situations
where it may not otherwise be possible, for example, in C. The main
idea is to minimize the number of errors and still maintain program
correctness. As with all tools, they must be used properly.
One incorrect use of TRy-except is to serve as a giant bandage over
large pieces of code. By that we mean putting large blocks, if not your
entire source code, within a try and/or have a large generic except to
"filter" any fatal errors by ignoring them:
# this is really bad code
try:
large_block_of_code # bandage of large piece of code
except Exception: # same as except:
pass # blind eye ignoring all errors
Obviously, errors cannot be avoided, and the job of TRy-except is to
provide a mechanism whereby an acceptable problem can be remedied
or properly dealt with, and not be used as a filter. The construct above
will hide many errors, but this type of usage promotes a poor
engineering practice that we certainly cannot endorse.
Bottom line: Avoid using try-except around a large block of code with
a pass just to hide errors. Instead, either handle specific exceptions
and ignore them (pass), or handle all errors and take a specific action.
Do not do both (handle all errors, ignore all errors).
10.3.6. "Exceptional Arguments"
No, the title of this section has nothing to do with having a major fight. Instead, we are referring to the
fact that an exception may have an argument or reason passed along to the exception handler when
they are raised. When an exception is raised, parameters are generally provided as an additional aid for