Erro ao atualizar o pip

Question

Eu preciso executar o seguinte comando

pip install --upgrade pip

mas recebendo a seguinte exceção

Exception:

Traceback (most recent call last):

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/basecommand.py", line 215, in main

status = self.run(options, args)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/commands/install.py", line 335, in run

wb.build(autobuilding=True)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/wheel.py", line 749, in build

self.requirement_set.prepare_files(self.finder)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/req/req_set.py", line 380, in prepare_files

ignore_dependencies=self.ignore_dependencies))

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/req/req_set.py", line 487, in _prepare_file

req_to_install, finder)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/req/req_set.py", line 428, in _check_skip_installed

req_to_install, upgrade_allowed)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/index.py", line 465, in find_requirement

all_candidates = self.find_all_candidates(req.name)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/index.py", line 423, in find_all_candidates

for page in self._get_pages(url_locations, project_name):

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/index.py", line 568, in _get_pages

page = self._get_page(location)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/index.py", line 683, in _get_page

return HTMLPage.get_page(link, session=self.session)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/index.py", line 792, in get_page

"Cache-Control": "max-age=600",

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/_vendor/requests/sessions.py", line 488, in get

return self.request('GET', url, **kwargs)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/download.py", line 386, in request

return super(PipSession, self).request(method, url, *args, **kwargs)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/_vendor/requests/sessions.py", line 475, in request

resp = self.send(prep, **send_kwargs)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/_vendor/requests/sessions.py", line 596, in send

r = adapter.send(request, **kwargs)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/_vendor/cachecontrol/adapter.py", line 47, in send

resp = super(CacheControlAdapter, self).send(request, **kw)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/_vendor/requests/adapters.py", line 390, in send

conn = self.get_connection(request.url, proxies)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/_vendor/requests/adapters.py", line 290, in get_connection

proxy_manager = self.proxy_manager_for(proxy)

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/_vendor/requests/adapters.py", line 184, in proxy_manager_for

**proxy_kwargs

File "/home/krishna/anaconda3/lib/python3.6/site-packages/pip/_vendor/requests/packages/urllib3/contrib/socks.py", line 154, in init

"Unable to determine SOCKS version from %s" % proxy_url

ValueError: Unable to determine SOCKS version from

Eu instalei o python 3.6 com força no Ubuntu 16.04 recém-instalado. Isso está acontecendo devido a esse motivo?

Como pode executar o comando?