matlab - How to get accurate time stamps from the computer?

I'm working in matlab and I need to get a very precise time measurement.
The accuracy I need is at least 1ms (and preferably much better than that).
It needs to be a timestamp and not just a duration measurement, because I need it for clock synchronization.
Answers for python can also help.

For clarification - I know how to get the current time. My problem is with the accuracy. As far as I know, the "clock" function is not accurate enough.