jflory  (e) brainzutils-python   master  ~  git  metabrainz  brainzutils-python  pip3 install psycopg2==2.7.3.2
Collecting psycopg2==2.7.3.2
  Downloading psycopg2-2.7.3.2-cp36-cp36m-manylinux1_x86_64.whl (2.7MB)
    100% |████████████████████████████████| 2.7MB 432kB/s 
Installing collected packages: psycopg2
Successfully installed psycopg2-2.7.3.2
 jflory  (e) brainzutils-python   master  ~  git  metabrainz  brainzutils-python  pip3 install psycopg2==2.6.1
Collecting psycopg2==2.6.1
  Using cached psycopg2-2.6.1.tar.gz
    Complete output from command python setup.py egg_info:
    running egg_info
    creating pip-egg-info/psycopg2.egg-info
    writing pip-egg-info/psycopg2.egg-info/PKG-INFO
    writing dependency_links to pip-egg-info/psycopg2.egg-info/dependency_links.txt
    writing top-level names to pip-egg-info/psycopg2.egg-info/top_level.txt
    writing manifest file 'pip-egg-info/psycopg2.egg-info/SOURCES.txt'
    Error: pg_config executable not found.
    
    Please add the directory containing pg_config to the PATH
    or specify the full executable path with the option:
    
        python setup.py build_ext --pg-config /path/to/pg_config build ...
    
    or with the pg_config option in 'setup.cfg'.
    
    ----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-q60l2v6c/psycopg2/