I installed MySQL and Python with Homebrew on OS X 10.10.5 Yosemite. My Python 2.7 is at python -> ../Cellar/pyth
You need to use dev version of mysqlclient:
pip install git+https://github.com/PyMySQL/mysqlclient-python.git@master
Before I had the lastest PyPI version (1.3.7) on Python 3.4 and it was searching for libmysqlclient.18.dylib (from MySQL 5.6) whereas I had only libmysqlclient.20.dylib(from MySQL 5.7).
If you use Python 3, MySQL-python is not an option (and mysqlclient is its newer version).