I followed a guide to get my python flask app running and I am at the last step where I change http into https with certbot. But when I run my certbot command sudo certbot --nginx -d domainname -d www.domainname I get ModuleNotFoundError: No module named '_cffi_backend'
The whole error is:
Traceback (most recent call last):
File "/usr/bin/certbot", line 11, in <module>
load_entry_point('certbot==0.31.0', 'console_scripts', 'certbot')()
File "/home/mc-obfuscator/.local/lib/python3.8/site-packages/pkg_resources/__init__.py", line 490, in load_entry_point
return get_distribution(dist).load_entry_point(group, name)
File "/home/mc-obfuscator/.local/lib/python3.8/site-packages/pkg_resources/__init__.py", line 2859, in load_entry_point
return ep.load()
File "/home/mc-obfuscator/.local/lib/python3.8/site-packages/pkg_resources/__init__.py", line 2450, in load
return self.resolve()
File "/home/mc-obfuscator/.local/lib/python3.8/site-packages/pkg_resources/__init__.py", line 2456, in resolve
module = __import__(self.module_name, fromlist=['__name__'], level=0)
File "/usr/lib/python3/dist-packages/certbot/main.py", line 10, in <module>
import josepy as jose
File "/usr/lib/python3/dist-packages/josepy/__init__.py", line 44, in <module>
from josepy.interfaces import JSONDeSerializable
File "/usr/lib/python3/dist-packages/josepy/interfaces.py", line 8, in <module>
from josepy import errors, util
File "/usr/lib/python3/dist-packages/josepy/util.py", line 4, in <module>
import OpenSSL
File "/usr/lib/python3/dist-packages/OpenSSL/__init__.py", line 8, in <module>
from OpenSSL import crypto, SSL
File "/usr/lib/python3/dist-packages/OpenSSL/crypto.py", line 12, in <module>
from cryptography import x509
File "/usr/lib/python3/dist-packages/cryptography/x509/__init__.py", line 8, in <module>
from cryptography.x509.base import (
File "/usr/lib/python3/dist-packages/cryptography/x509/base.py", line 16, in <module>
from cryptography.x509.extensions import Extension, ExtensionType
File "/usr/lib/python3/dist-packages/cryptography/x509/extensions.py", line 18, in <module>
from cryptography.hazmat.primitives import constant_time, serialization
File "/usr/lib/python3/dist-packages/cryptography/hazmat/primitives/constant_time.py", line 9, in <module>
from cryptography.hazmat.bindings._constant_time import lib
ModuleNotFoundError: No module named '_cffi_backend'
I hope someone can help as I have found a lot of people asking questions about this mysterious _cffi_backend thing.
Some more info:
If I do python3 -m pip install cffi it says requirement already satisfied.
I have also gotten this error when installing other things and trying different peoples solutions.
'ModuleNotFoundError: No module named 'apt_pkg'
that seems to be fixed by doing sudo apt-get install python3-apt --reinstall but now I get: ImportError: cannot import name '_gi' from partially initialized module 'gi' (most likely due to a circular import) (/usr/lib/python3/dist-packages/gi/__init__.py)
I also made a symbolic link with /usr/lib/python3/dist-packages/apt_pkg.so -> apt_pkg.cpython-36m-x86_64-linux-gnu.so
something other people said would work. I am running python 3.8 but probably have 3.6 on the server as well. If I do python it opens the 3.8 shell. Also I am running ubuntu 18.04.4.
ls -al /usr/bin | grep python
gives :
-rwxr-xr-x 1 root root 1056 Apr 16 2018 dh_python2
lrwxrwxrwx 1 root root 23 Nov 7 10:07 pdb2.7 -> ../lib/python2.7/pdb.py
lrwxrwxrwx 1 root root 23 Nov 7 10:44 pdb3.6 -> ../lib/python3.6/pdb.py
lrwxrwxrwx 1 root root 23 Nov 7 10:50 pdb3.7 -> ../lib/python3.7/pdb.py
lrwxrwxrwx 1 root root 23 Oct 28 16:14 pdb3.8 -> ../lib/python3.8/pdb.py
lrwxrwxrwx 1 root root 31 Oct 25 2018 py3versions -> ../share/python3/py3versions.py
lrwxrwxrwx 1 root root 24 Jun 19 2019 python -> /etc/alternatives/python
lrwxrwxrwx 1 root root 16 Apr 16 2018 python-config -> python2.7-config
lrwxrwxrwx 1 root root 9 Apr 16 2018 python2 -> python2.7
lrwxrwxrwx 1 root root 16 Apr 16 2018 python2-config -> python2.7-config
-rwxr-xr-x 1 root root 3637096 Nov 7 10:07 python2.7
lrwxrwxrwx 1 root root 33 Nov 7 10:07 python2.7-config -> x86_64-linux-gnu-python2.7-config
lrwxrwxrwx 1 root root 25 Jan 5 10:38 python3 -> /etc/alternatives/python3
-rwxr-xr-x 1 root root 384 Feb 5 2018 python3-futurize
-rwxr-xr-x 1 root root 388 Feb 5 2018 python3-pasteurize
-rwxr-xr-x 1 root root 152 Nov 11 2017 python3-pbr
-rwxr-xr-x 2 root root 4526456 Nov 7 10:44 python3.6
-rwxr-xr-x 2 root root 4526456 Nov 7 10:44 python3.6m
-rwxr-xr-x 2 root root 4873376 Nov 7 10:50 python3.7
-rwxr-xr-x 2 root root 4873376 Nov 7 10:50 python3.7m
-rwxr-xr-x 1 root root 5203488 Oct 28 16:14 python3.8
lrwxrwxrwx 1 root root 10 Oct 25 2018 python3m -> python3.6m
lrwxrwxrwx 1 root root 29 Apr 16 2018 pyversions -> ../share/python/pyversions.py
lrwxrwxrwx 1 root root 10 Sep 27 2018 uwsgi_python36 -> uwsgi-core
lrwxrwxrwx 1 root root 33 Apr 16 2018 x86_64-linux-gnu-python-config -> x86_64-linux-gnu-python2.7-config
-rwxr-xr-x 1 root root 2971 Nov 7 10:07 x86_64-linux-gnu-python2.7-config
The files do exist on my system because:
dpkg -l python3-cffi-backend python3-cryptography
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-=====================================================-===============================-===============================-===============================================================================================================
ii python3-cffi-backend 1.11.5-1 amd64 Foreign Function Interface for Python 3 calling C code - runtime
ii python3-cryptography 2.1.4-1ubuntu1.3 amd64 Python library exposing cryptographic recipes and primitives (Python 3)
This fixes the problem:
pip install -U cffi