Regex: positive lookbehind

[scidam]

Is there a way to read in text_lines to look exactly like in the csv files so that my regex expression work?

Do you want to read the file in line-by-line fashion?
Probably, you don't need to use regexp here at all, e.g.

for line in f:
    index = line.find('model choice :')
    if index > 0
        index += len('model choice :') 
        what_you_need = line[index:]