Postgresql 在 MacOS 10.9.5 上安装 Psycopg2 时出错

I'm trying to install Psycopg2 on my Macbook, but I am getting an error. I found a lot of the same questions on StackOverflow but no answer seems to work.
I'm using:

OS: MacOS 10.9.5
Python Version: 3.4.3

我的错误代码是:

Running setup.py egg_info for package psycopg2  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'.  Complete output from
command python setup.py egg_info:  running egg_info

writing pip-egg-info/psycopg2.egg-info/PKG-INFO
 
writing top-level names to
pip-egg-info/psycopg2.egg-info/top_level.txt
 
writing dependency_links to
pip-egg-info/psycopg2.egg-info/dependency_links.txt
 
warning: manifest_maker: standard file '-c' not found
 
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
/Users/sg/build/psycopg2 Storing complete log in
/Users/sg/Library/Logs/pip.log