TypeError：无法腌制时间对象

Question

After running code from my previous question , I get a result set from my subprocess that looks like this:

[[(<PyTime:6/10/2012 3:24:17 AM>, 1593.5, 413.0, 19.600000381469727, 430.0, 16.0, 47.0, 42.70000076293945, 15.600000381469727, 69.5), 
(<PyTime:6/10/2012 3:24:18 AM>, 1658.0, 412.0, 19.600000381469727, 429.0, 7.0, 34.400001525878906, 30.899999618530273, 15.699999809265137, 69.5), 
(<PyTime:6/10/2012 3:24:19 AM>, 1685.0, 406.0, 19.600000381469727, 425.0, 18.0, 28.700000762939453, 26.399999618530273, 15.699999809265137, 69.5)]]

When I attempt to send this from my subprocess to my parent process, I do this, where cu equals the above.

conn.send(pickle.dumps(cu))

This results in the following error: TypeError: can't pickle time objects

What is a work around to send the above list back to the parent process?

Answer 1

As the other answers said, PyTime objects aren't "pickleable". I would suggest converting them to regular datetime objects, which can be pickle:

from datetime import datetime

list_of_pytimes = [ ... ]
list_of_datetimes = [datetime.fromtimestamp(int(pytime)) for pytime in list_of_pytimes]
# Now this will work
pickle.dumps(list_of_datetimes)

Answer 2

Those PyTime objects do not look like the datetime objects from Python's standard library. Since normal datetime objects appear to pickle without issue, I would recommend converting them. I don't know what database driver you're using, but you may be able to configure it to use standard datetime objects.

Answer 3

Try monkey-patching PyTime class with __getstate__ and __setstate__ ( documentation ). If that doesn't work you'll have to convert to a pickleable type eg datetime.time .