title: ImportError: No module named dash
body: <p>I am unable to install dash in production server. In local, I have imported by </p>
  
  <pre><code>pip install dash==0.29.0
  </code></pre>
  
  <p>But in prod it is not working. When i am using </p>
  
  <pre><code>sudo apt-get install python dash
  </code></pre>
  
  <p>its showing </p>
  
  <pre><code>&gt; "dash is already the newest version (0.5.8-2.4)"
  </code></pre>
  
  <p>, however while using import dash am getting </p>
  
  <pre><code>&gt; "ImportError: No module named dash"
  </code></pre>
  
  <p>have also tried </p>
  
  <blockquote>
    <p>sudo pip install python dash==0.29.0 </p>
  </blockquote>
  
  <p>but it gives below error:</p>
  
  <pre><code>Requirement already satisfied: python in /usr/lib/python2.7/lib-dynload
  Collecting dash==0.29.0
  Exception:
  Traceback (most recent call last):
    File "/usr/lib/python2.7/dist-packages/pip/basecommand.py", line 215, in main
      status = self.run(options, args)
    File "/usr/lib/python2.7/dist-packages/pip/commands/install.py", line 353, in run
      wb.build(autobuilding=True)
    File "/usr/lib/python2.7/dist-packages/pip/wheel.py", line 749, in build
      self.requirement_set.prepare_files(self.finder)
    File "/usr/lib/python2.7/dist-packages/pip/req/req_set.py", line 380, in prepare_files
      ignore_dependencies=self.ignore_dependencies))
    File "/usr/lib/python2.7/dist-packages/pip/req/req_set.py", line 554, in _prepare_file
      require_hashes
    File "/usr/lib/python2.7/dist-packages/pip/req/req_install.py", line 278, in populate_link
      self.link = finder.find_requirement(self, upgrade)
    File "/usr/lib/python2.7/dist-packages/pip/index.py", line 465, in find_requirement
      all_candidates = self.find_all_candidates(req.name)
    File "/usr/lib/python2.7/dist-packages/pip/index.py", line 423, in find_all_candidates
      for page in self._get_pages(url_locations, project_name):
    File "/usr/lib/python2.7/dist-packages/pip/index.py", line 568, in _get_pages
      page = self._get_page(location)
    File "/usr/lib/python2.7/dist-packages/pip/index.py", line 683, in _get_page
      return HTMLPage.get_page(link, session=self.session)
    File "/usr/lib/python2.7/dist-packages/pip/index.py", line 792, in get_page
      "Cache-Control": "max-age=600",
    File "/usr/share/python-wheels/requests-2.12.4-py2.py3-none-any.whl/requests/sessions.py", line 501, in get
      return self.request('GET', url, **kwargs)
    File "/usr/lib/python2.7/dist-packages/pip/download.py", line 386, in request
      return super(PipSession, self).request(method, url, *args, **kwargs)
    File "/usr/share/python-wheels/requests-2.12.4-py2.py3-none-any.whl/requests/sessions.py", line 488, in request
      resp = self.send(prep, **send_kwargs)
    File "/usr/share/python-wheels/requests-2.12.4-py2.py3-none-any.whl/requests/sessions.py", line 609, in send
      r = adapter.send(request, **kwargs)
    File "/usr/share/python-wheels/CacheControl-0.11.7-py2.py3-none-any.whl/cachecontrol/adapter.py", line 47, in send
      resp = super(CacheControlAdapter, self).send(request, **kw)
    File "/usr/share/python-wheels/requests-2.12.4-py2.py3-none-any.whl/requests/adapters.py", line 423, in send
      timeout=timeout
    File "/usr/share/python-wheels/urllib3-1.19.1-py2.py3-none-any.whl/urllib3/connectionpool.py", line 643, in urlopen
      _stacktrace=sys.exc_info()[2])
    File "/usr/share/python-wheels/urllib3-1.19.1-py2.py3-none-any.whl/urllib3/util/retry.py", line 315, in increment
      total -= 1
  TypeError: unsupported operand type(s) for -=: 'Retry' and 'int'
  </code></pre>