If you try to install psycopg2 on a Greenplum system using pip you may run into this error:
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'.
The solution is to add the path to the Greenplum bin directory to your environment PATH.
Then run pip install psycopg2 and all should be good.