title: How to fix urllib3 RuntimeError: Requests dependency 'urllib3' must be version >= 1.21.1, < 1.22?
body: <p>I am a new developer and learning to code in Python 3.4.2. I am running Debian linux on a Raspberry Pi3. After the fresh install I did both</p>
  
  <pre><code>sudo apt-get update
  </code></pre>
  
  <p>and </p>
  
  <pre><code>sudo apt-get upgrade
  </code></pre>
  
  <p>to get everything up to date.</p>
  
  <p>I am trying to test a section of code which uploads a file to Dropbox:</p>
  
  <pre><code>import dropbox
  import urllib3
  
  authkey = (my dropbox dev auth key)
  
  with open('test.csv','rb') as f:
      dbx = dropbox.Dropbox(authkey)
      dbx.files_upload(f.read(), '/test.csv')
  </code></pre>
  
  <p>Now, I have no idea if the actual Dropbox code is correct, because I am getting the following error when I run the script in the Python shell:</p>
  
  <pre><code>Traceback (most recent call last):
    File "/usr/local/lib/python3.4/dist-packages/requests/__init__.py", line 58, in &lt;module&gt;
      assert minor &gt;= 21
  AssertionError
  
  During handling of the above exception, another exception occurred:
  
  Traceback (most recent call last):
    File "/home/pi/dbtest.py", line 1, in &lt;module&gt;
      import dropbox
    File "/usr/local/lib/python3.4/dist-packages/dropbox/__init__.py", line 3, in &lt;module&gt;
      from .dropbox import __version__, Dropbox, DropboxTeam, create_session  # noqa: F401
    File "/usr/local/lib/python3.4/dist-packages/dropbox/dropbox.py", line 18, in &lt;module&gt;
      import requests
    File "/usr/local/lib/python3.4/dist-packages/requests/__init__.py", line 61, in &lt;module&gt;
      raise RuntimeError('Requests dependency \'urllib3\' must be version &gt;= 1.21.1, &lt; 1.22!')
  RuntimeError: Requests dependency 'urllib3' must be version &gt;= 1.21.1, &lt; 1.22!
  </code></pre>
  
  <p>To me this indicates that I have an issue with my urllib3 install, so I go to the bash shell and type:</p>
  
  <pre><code>sudo pip3 install --update urllib3
  </code></pre>
  
  <p>And get the exact same error message:</p>
  
  <pre><code>Traceback (most recent call last):
    File "/usr/local/lib/python3.4/dist-packages/requests/__init__.py", line 58, in &lt;module&gt;
      assert minor &gt;= 21
  AssertionError
  
  During handling of the above exception, another exception occurred:
  
  Traceback (most recent call last):
    File "/usr/bin/pip3", line 9, in &lt;module&gt;
      load_entry_point('pip==1.5.6', 'console_scripts', 'pip3')()
    File "/usr/lib/python3/dist-packages/pkg_resources.py", line 356, in load_entry_point
      return get_distribution(dist).load_entry_point(group, name)
    File "/usr/lib/python3/dist-packages/pkg_resources.py", line 2476, in load_entry_point
      return ep.load()
    File "/usr/lib/python3/dist-packages/pkg_resources.py", line 2190, in load
      ['__name__'])
    File "/usr/lib/python3/dist-packages/pip/__init__.py", line 74, in &lt;module&gt;
      from pip.vcs import git, mercurial, subversion, bazaar  # noqa
    File "/usr/lib/python3/dist-packages/pip/vcs/mercurial.py", line 9, in &lt;module&gt;
      from pip.download import path_to_url
    File "/usr/lib/python3/dist-packages/pip/download.py", line 22, in &lt;module&gt;
      import requests, six
    File "/usr/local/lib/python3.4/dist-packages/requests/__init__.py", line 61, in &lt;module&gt;
      raise RuntimeError('Requests dependency \'urllib3\' must be version &gt;= 1.21.1, &lt; 1.22!')
  RuntimeError: Requests dependency 'urllib3' must be version &gt;= 1.21.1, &lt; 1.22!
  </code></pre>
  
  <p>I have other scripts that use Twilio to send SMS messages and they are no longer working either, yielding the same error message referencing urllib3 version issues.</p>
  
  <p>Can anyone help me resolve this issue or point me in the right direction?</p>
  
  <p>Thank you very much.</p>