Timer with subtimers in Python

timer.py

from sys import stdout
from time import time
from collections import OrderedDict


class Timer:
    def __init__(self, autoshow=False):
        self.subs = OrderedDict()
        self.autoshow = autoshow

    def __enter__(self):
        self._start_time = time()
        return self

    def __exit__(self, *args, **kwargs):
        self.time = time() - self._start_time
        if self.autoshow:
            self.show()

    def sub(self, name):
        res = Timer()
        self.subs[name] = res
        return res

    def show(self, name='Total', indent=0, output=stdout):
        prefix = "  "*indent
        print >>output, prefix, '*', name, ":", self.time
        for name, val in self.subs.iteritems():
            val.show(name, indent+1)

if __name__ == "__main__":
    from time import sleep
    with Timer(True) as t:
        sleep(1)
        with t.sub('Lol') as t1:
            sleep(1)
            with t1.sub('haha'):
                pass
        with t.sub('Q'):
            sleep(0.5)