test.py

#!/bin/env python
# -*- coding: utf-8 -*-

from timeit import timeit


class Fib:
    def __init__(self, end):
        self.a = 0
        self.b = 1
        self.cur = 0
        self.end = end

    def __iter__(self):

        return self

    def next(self):
        if self.cur == self.end:

            raise StopIteration

        self.cur += 1
        self.a, self.b = self.b, self.a + self.b

        return self.a

exception = '''\
try:
    d[1]
except KeyError:
    1
'''

bad_key = 'd={-x: x for x in xrange(1000000)}'
good_key = 'd={x: x for x in xrange(1000000)}'


def main():
    print timeit('d.get(1, 1)', bad_key, number=1000000)
    print timeit('d.get(1, 1)', good_key, number=1000000)
    print timeit(exception, bad_key, number=1000000)
    print timeit(exception, good_key, number=1000000)
    print timeit('d[1] if 1 in d else 1', bad_key, number=1000000)
    print timeit('d[1] if 1 in d else 1', good_key, number=1000000)
    for x in Fib(5):
        print x

    print numberxt(Fib(3))

if __name__ == '__main__':
    main()