How to get line numbers of the snippets matching a regexp?

Question

How is it possible to obtain the line numbers of all the text snippets matching a given regexp, within a file?

file_content = f.rea         


        

Answer 1

 with open(somefile, 'r') as f:
     line_numbers = [n for n, line in enumerate(f) if re.search(someRegexp, line)]