Python regex for this string

Simply use re.split. Probably the most intuitive method.

>>> import re
>>> re.split(r'[\(\)]', "111(A5)A05209(May)2005")
['111', 'A5', 'A05209', 'May', '2005']

The easiest

s = " 111(A5)A05209(May)2005"
s.replace('(', ' ').replace(')', ' ')
values = s.split()
>> ['111', 'A5', 'A05209', 'May', '2005']

The regexp way would be

import re
s = re.findall(r'\w+', s)
>> ['111', 'A5', 'A05209', 'May', '2005']

Use re.findall and str.join:

>>> import re
>>> strs = "111(A5)A05209(May)2005"
>>> print "\n".join(re.findall(r'\w+',strs))
111
A5
A05209
May
2005

or re.sub:

>>> print re.sub(r'[\W]+','\n',strs)
111
A5
A05209
May
2005

Another alternative is str.translate:

>>> from string import punctuation, whitespace, maketrans
>>> intab = punctuation + whitespace
>>> outtab = "\n"*len(intab)
>>> print strs.translate(trantab)
111
A5
A05209
May
2005

In terms of performance str.translate is far better than regex:

>>> strs = "111(A5)A05209(May)2005"*1000
>>> %timeit "\n".join(re.findall(r'\w+',strs))
100 loops, best of 3: 2.19 ms per loop
>>> %timeit re.sub(r'[\W]+','\n',strs)
100 loops, best of 3: 4.43 ms per loop
>>> %timeit strs.translate(trantab)
10000 loops, best of 3: 93.9 us per loop

>>> str = '111(A5)A05209(May)2005'
>>> print str.replace('(','\n').replace(')','\n')
111
A5
A05209
May
2005