Certbot: Certbot verwendet eine alte Version von Python

Hallo zusammen, Certbot auf Ubuntu 14.04 verwendet eine alte Version von Pip (8.0.3), auch wenn die neueste Version von Pip (9.0.1) verfügbar ist. Ich kann den Befehl $certbot-auto renew nicht erfolgreich ausführen, da er die Warnung InsecurePlatformWarning ausgibt. Kann ich das beheben? Darunter habe ich die gesamte Ausgabe eingefügt:

Command "/home/wolthuis/.local/share/letsencrypt/bin/python2.7 -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-Txn1F9/cryptography/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('
', '
'), __file__, 'exec'))" install --record /tmp/pip-igOc6P-record/install-record.txt --single-version-externally-managed --compile --install-headers /home/wolthuis/.local/share/letsencrypt/include/site/python2.7/cryptography" failed with error code 1 in /tmp/pip-build-Txn1F9/cryptography
/home/wolthuis/.local/share/letsencrypt/local/lib/python2.7/site-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:120: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning.
  InsecurePlatformWarning
You are using pip version 8.0.3, however version 9.0.1 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.
=====================================================

Certbot has problem setting up the virtual environment.

Based on your pip output, the problem can likely be fixed by 
increasing the available memory.

Consult https://certbot.eff.org/docs/install.html#problems-with-python-virtual-environment
for possible solutions.
You may also find some support resources at https://certbot.eff.org/support/ .