with open('SCC.txt') as data:
    process_line = lambda line, r: (int(line.rstrip().split()[r]), int(line
        .rstrip().split()[1 - r]))
edge_list, reverved_edge_list = map(list, zip(*[(process_line(line, 0),
    process_line(line, 1)) for line in data if line.rstrip()]))
Build 2 lists in one go while reading from file, pythonically