How to split a string using an empty separator in Python

Use list():

>>> list('1111')
['1', '1', '1', '1']

Alternatively, you can use map() (Python 2.7 only):

>>> map(None, '1111')
['1', '1', '1', '1']

Time differences:

$ python -m timeit "list('1111')"
1000000 loops, best of 3: 0.483 usec per loop
$ python -m timeit "map(None, '1111')"
1000000 loops, best of 3: 0.431 usec per loop