Exercise 1 solution

    import re

    log = "GET /a 200 12ms; POST /b 404 8ms; GET /c 200 130ms"
    rec = re.compile(r"(?P<method>[A-Z]+) (?P<path>/\w+) (?P<status>\d{3}) (?P<ms>\d+)ms")

    total = 0
    for m in rec.finditer(log):
        print(m["method"], m["path"], m.start())
        total += int(m["ms"])
    print(total)
    # GET /a 0
    # POST /b 17
    # GET /c 34
    # 150

(All lines were run and printed exactly what is shown.)

Explanation: finditer yields a match object per record, so m.start() gives the
position and m["name"] gives each named group. The group text is a string, so
it is converted with int() before adding. findall could not report the
positions.