Collecting rpkg==1.53
  1 location(s) to search for versions of rpkg:
  * https://pypi.python.org/simple/rpkg/
  Getting page https://pypi.python.org/simple/rpkg/
  Analyzing links from page https://pypi.python.org/simple/rpkg/
    Skipping link https://pypi.python.org/packages/97/ec/fac0fa31181d0a606e96db2e0103caf29c1e233a7978b3548517fa627240/rpkg-1.52-py2-none-any.whl#md5=3196619e6e94b989a482767401673a2a (from https://pypi.python.org/simple/rpkg/); it is not compatible with this Python
    Found link https://pypi.python.org/packages/5e/9d/d49e41dec54b7dbf437f6d7db03c10df35202c297a6b8aba7e34cb35a3f3/rpkg-1.52-py3-none-any.whl#md5=a539010be64dc3ca576f0b7a2baf891d (from https://pypi.python.org/simple/rpkg/), version: 1.52
    Found link https://pypi.python.org/packages/15/83/6474c1e752621e4e2eaa35070a1b7e1cacb42b5ee15ab3c2c6d83aba3410/rpkg-1.52.tar.gz#md5=847c8def02f30a4007c0940c6fd53b9e (from https://pypi.python.org/simple/rpkg/), version: 1.52
    Found link https://pypi.python.org/packages/60/4f/3ac7eac281db7fabaf71993853ccf4a066e885295b5cb005f5bd9de27a54/rpkg-1.53-py2.py3-none-any.whl#md5=7fab07ec7f039de66d936df7502aee95 (from https://pypi.python.org/simple/rpkg/), version: 1.53
    Found link https://pypi.python.org/packages/16/80/89b7415407a59ff859a586a674f2c2f8c0e3c5c969022a9fa9c76825ed6f/rpkg-1.53.tar.gz#md5=5aeb3b350bb569a8ad739d5a12d8107b (from https://pypi.python.org/simple/rpkg/), version: 1.53
  Using version 1.53 (newest of versions: 1.53)
  Downloading rpkg-1.53-py2.py3-none-any.whl (59kB)
  Downloading from URL https://pypi.python.org/packages/60/4f/3ac7eac281db7fabaf71993853ccf4a066e885295b5cb005f5bd9de27a54/rpkg-1.53-py2.py3-none-any.whl#md5=7fab07ec7f039de66d936df7502aee95 (from https://pypi.python.org/simple/rpkg/)
  Saved /tmp/tmpvnnmja_a/rpkg-1.53-py2.py3-none-any.whl
Skipping rpkg, due to already being wheel.
Cleaning up...
  Removing source in /tmp/pip-build-kuuhjz05/rpkg