pbr version conflict

[jeffkit]

`Installed /home/ubuntu/venv/fabuloso/lib/python2.7/site-packages/fabuloso-1.3-py2.7.egg
Processing dependencies for fabuloso==1.3
Searching for pbr<1.0,>=0.5.21
Reading https://pypi.python.org/simple/pbr/
Best match: pbr 0.11.1
Downloading https://pypi.python.org/packages/source/p/pbr/pbr-0.11.1.tar.gz#md5=dc476e5ffe4e15dfecbdf5586fadc8db
Processing pbr-0.11.1.tar.gz
Writing /tmp/easy_install-6ihKqT/pbr-0.11.1/setup.cfg
Running pbr-0.11.1/setup.py -q bdist_egg --dist-dir /tmp/easy_install-6ihKqT/pbr-0.11.1/egg-dist-tmp-WLEiWW
creating /home/ubuntu/venv/fabuloso/lib/python2.7/site-packages/pbr-0.11.1-py2.7.egg
Extracting pbr-0.11.1-py2.7.egg to /home/ubuntu/venv/fabuloso/lib/python2.7/site-packages
Adding pbr 0.11.1 to easy-install.pth file
Installing pbr script to /home/ubuntu/venv/fabuloso/bin

Installed /home/ubuntu/venv/fabuloso/lib/python2.7/site-packages/pbr-0.11.1-py2.7.egg
error: pbr 0.11.1 is installed but pbr>=1.6 is required by set(['stevedore', 'debtcollector'])
`

fabuloso required pbr < 1.0, > 0.5.21, but the stevedore, debtcollector required pbr >= 1.6.

how to fix this conflict?