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It is a somewhat common pattern to write:
 try:
 do_something()
 except SomeException:
 pass
To search examples in the standard library (or any other code base) use:
 $ egrep -C2 "except( [A-Za-z]+)?:" *py | grep -C2 "pass"
In the Python2.7 Lib directory alone, we find 213 examples.
I suggest a context manager be added that can ignore specifie exceptions. Here's a possible implementation:
class Ignore:
 ''' Context manager to ignore particular exceptions'''
 def __init__(self, *ignored_exceptions):
 self.ignored_exceptions = ignored_exceptions
 def __enter__(self):
 return self
 def __exit__(self, exctype, excinst, exctb):
 return exctype in self.ignored_exceptions
The usage would be something like this:
 with Ignore(IndexError, KeyError):
 print(s[t])
Here's a real-world example taken from zipfile.py:
 def _check_zipfile(fp):
 try:
 if _EndRecData(fp):
 return True # file has correct magic number 
 except IOError:
 pass
 return False
With Ignore() context manager, the code cleans-up nicely:
 def _check_zipfile(fp):
 with Ignore(IOError):
 return bool(EndRecData(fp)) # file has correct magic number 
 return False
I think this would make a nice addition to contextlib.