Regex Python with order for OR | pattern -

how can return ordered list regex? still kind of learning regex.

for example, lets have list = [a,b,c,c,b,a,g] , want have b's first, followed a's, lastly a's in list. how can regex it?

i thinking: pattern = re.compile('b|c|a') [letter letter in list if pattern.match(letter)]

but comes out ['a','b','c','c','b','a']

what want ['b','b','c','c','a','a']

how possible? thanks!

regular expressions dealing patterns in text, search , extract substrings string. want actual intelligent processing. outside scope of regex put quite easy in python :)

you make sound there should 'a', 'b', or 'c' in list can write simple comparison function

def cmp(c):     return {'a' : 1, 'b' : 0, 'c' : 2}[c] 

then give sorted

sorted(your_list, key=cmp) 

simple that.