test_session.py

>>> def ints1(lst):
...   return [int(x) for x in lst if x.isdigit()]
...
>>> def ints2(lst):
...   out = []
...   for item in lst:
...     try:
...       out.append(int(item))
...     except ValueError:
...       pass
...   return out
...
>>> ints1(['a', '1'])
[1]
>>> ints2(['a', '1'])
[1]
>>> import timeit
>>> timeit.timeit(setup='from __main__ import *', stmt='ints1(["1", "2", "a", "b"])')
2.519864082336426
>>> timeit.timeit(setup='from __main__ import *', stmt='ints2(["1", "2", "a", "b"])')
9.285669088363647