Traceback (most recent call last):


 "/opt/certbot/bin/pip", line 7, in <module>

from pip._internal.cli.main import main


 "/opt/certbot/lib/python3.5/site-packages/pip/_internal/cli/main.py", line 60

sys.stderr.write(f"ERROR: {exc}")

^
SyntaxError: invalid syntax

Traceback (most recent call last):

 "/usr/share/w3af/w3af/core/ui/gui/main.py", line 917, in _proxy_tool
ProxiedRequests(self.w3af)

 "/usr/share/w3af/w3af/core/ui/gui/tools/proxywin.py", line 158, in __init__
self.reload_options()

 "/usr/share/w3af/w3af/core/ui/gui/tools/proxywin.py", line 254, in reload_options
self._start_proxy()

 "/usr/share/w3af/w3af/core/ui/gui/tools/proxywin.py", line 308, in _start_proxy
self.proxy = InterceptProxy(ip, int(port), self.w3af.uri_opener)

 "/usr/share/w3af/w3af/core/controllers/daemons/proxy/intercept_proxy.py", line 48, in __init__
name='LocalProxyThread')

 "/usr/share/w3af/w3af/core/controllers/daemons/proxy/proxy.py", line 122, in __init__
port=port)

 "/usr/share/w3af/mitmproxy/proxy/config.py", line 106, in __init__
sslversion_choices[ssl_version_client]KeyError: 'SSLv23'