Does Python have sync?

As said, Python 3.3 has the call - on Python 2.x, since it is a simple system call, requiring no data to be passed back and forth, you can use ctypes to make the call:

>>> import ctypes
>>> libc = ctypes.CDLL("libc.so.6")
>>> libc.sync()
0

Python 3.3 has os.sync, see the docs. The source confirms it is the same thing.

For Python 2 you can to make an external call to the system:

from subprocess import check_call
check_call(['sync'])