title: pip in virtualenv gets ConnectTimeoutError
body: <p>I'm current attempting to install packages in a python-3.4 virtualenv and I keep getting these Retry/TimeoutErrors.</p>
  
  <pre><code>(backend)root@XXXX:/var/virtualenvs# pip3 install -r backend-freeze.txt
  Collecting cassandra-driver==2.7.2 (from -r backend-freeze.txt (line 1))
    Retrying (Retry(total=4, connect=None, read=None, redirect=None)) after connection broken by 'ConnectTimeoutError(&lt;pip._vendor.requests.packages.urllib3.connection.VerifiedHTTPSConnection object at 0x7f4d7faf94a8&gt;, 'Connection to pypi.python.org timed out. (connect timeout=15)')': /simple/cassandra-driver/
    Retrying (Retry(total=3, connect=None, read=None, redirect=None)) after connection broken by 'ConnectTimeoutError(&lt;pip._vendor.requests.packages.urllib3.connection.VerifiedHTTPSConnection object at 0x7f4d7faf9588&gt;, 'Connection to pypi.python.org timed out. (connect timeout=15)')': /simple/cassandra-driver/
    Retrying (Retry(total=2, connect=None, read=None, redirect=None)) after connection broken by 'ConnectTimeoutError(&lt;pip._vendor.requests.packages.urllib3.connection.VerifiedHTTPSConnection object at 0x7f4d7faf9668&gt;, 'Connection to pypi.python.org timed out. (connect timeout=15)')': /simple/cassandra-driver/
    Retrying (Retry(total=1, connect=None, read=None, redirect=None)) after connection broken by 'ConnectTimeoutError(&lt;pip._vendor.requests.packages.urllib3.connection.VerifiedHTTPSConnection object at 0x7f4d7faf9748&gt;, 'Connection to pypi.python.org timed out. (connect timeout=15)')': /simple/cassandra-driver/
  </code></pre>
  
  <p>Not sure what's going on here. I'm not using a proxy (which seems to be the case for others who have stated their experience with similar/same error).</p>