I am using Ubuntu and have installed Python 2.7.5 and 3.4.0. In Python 2.7.5 I am able to successfully assign a variable x = Value('i', 2)
, but not in 3.4.0. I am getting:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/local/lib/python3.4/multiprocessing/context.py", line 132, in Value
from .sharedctypes import Value
File "/usr/local/lib/python3.4/multiprocessing/sharedctypes.py", line 10, in <
module>
import ctypes
File "/usr/local/lib/python3.4/ctypes/__init__.py", line 7, in <module>
from _ctypes import Union, Structure, Array
ImportError: No module named '_ctypes'
I just updated to 3.3.2 through installing the source of 3.4.0. It installed in /usr/local/lib/python3.4.
Did I update to Python 3.4 correctly?
One thing I noticed that Python 3.4 is installed in usr/local/lib, while Python 3.3.2 is still installed in usr/lib, so it was not overwritten.
Installing libffi-dev
and re-installing python3.7 fixed the problem for me.
to cleanly build py 3.7 libffi-dev
is required or else later stuff will fail
If using RHEL/Fedora:
yum install libffi-devel
or
sudo dnf install libffi-devel
If using Debian/Ubuntu:
sudo apt-get install libffi-dev