Sort a list of strings based on regular expression match

python, sorting

Solution

In [1]: def grp(pat, txt): 
   ...:     r = re.search(pat, txt)
   ...:     return r.group(0) if r else '&'

In [2]: y
Out[2]: 
['random text random text, can be anything blabla %A blabla',
 'random text random text, can be anything blabla %D blabla',
 'random text random text, can be anything blabla blabla %F',
 'random text random text, can be anything blabla blabla',
 'random text random text, %C can be anything blabla blabla']

In [3]: y.sort(key=lambda l: grp("%\w", l))

In [4]: y
Out[4]: 
['random text random text, can be anything blabla %A blabla',
 'random text random text, %C can be anything blabla blabla',
 'random text random text, can be anything blabla %D blabla',
 'random text random text, can be anything blabla blabla %F',
 'random text random text, can be anything blabla blabla']

Problem

I have a text file that looks a bit like: ``` random text random text, can be anything blabla %A blabla random text random text, can be anything blabla %D blabla random text random text, can be anything blabla blabla %F random text random text, can be anything blabla blabla random text random text, %C can be anything blabla blabla ``` When I `readlines()` it in, it becomes a list of sentences. Now I want this list to be sorted by the letter after the `%`. So basically, when the sort is applied to the above, it should look like: ``` random text random text, can be anything blabla %A blabla random text random text, %C can be anything blabla blabla random text random text, can be anything blabla %D blabla random text random text, can be anything blabla blabla %F random text random text, can be anything blabla blabla ``` Is there a good way to do this, or will I have to break each string in to tubles, and then move the letters to a specific column, and then sort using `key=operator.itemgetter(col)`? Thank you

Original source