It's not just a matter of making test_datetime "faster". I see it as a regression, since now it fails randomly on slow buildbots.

Maybe we should revert the change until a solution is found.

http://buildbot.python.org/all/builders/ARMv7%20Ubuntu%203.x/builds/1025/steps/test/logs/stdio

running: test_datetime (802 sec)
running: test_datetime (832 sec)
running: test_datetime (862 sec)
running: test_datetime (892 sec)
0:15:02 load avg: 2.30 [406/406/1] test_datetime crashed (Exit code 1)
Timeout (0:15:00)!
Thread 0x400b4110 (most recent call first):
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/datetime.py", line 394 in __new__
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/datetime.py", line 1519 in local
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/datetime.py", line 1522 in _mktime
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/datetime.py", line 1550 in timestamp
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/datetimetester.py", line 4836 in test_system_transitions
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/unittest/case.py", line 615 in run
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/unittest/case.py", line 663 in __call__
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/unittest/suite.py", line 122 in run
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/unittest/suite.py", line 84 in __call__
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/unittest/suite.py", line 122 in run
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/unittest/suite.py", line 84 in __call__
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/unittest/runner.py", line 176 in run
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/support/__init__.py", line 1896 in _run_suite
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/support/__init__.py", line 1940 in run_unittest
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/test_datetime.py", line 54 in test_main
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/libregrtest/runtest.py", line 172 in runtest_inner
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/libregrtest/runtest.py", line 130 in runtest
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/libregrtest/runtest_mp.py", line 71 in run_tests_slave
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/libregrtest/main.py", line 519 in _main
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/libregrtest/main.py", line 512 in main
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/libregrtest/main.py", line 587 in main
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/regrtest.py", line 46 in _main
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/regrtest.py", line 50 in <module>
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/runpy.py", line 85 in _run_code
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/runpy.py", line 193 in _run_module_as_main