Mac#

First try

$ sudo pip install gevent

If that fails with

gevent/libevent.h:9:19: error: event.h: No such file or directory

then do either of the following.

Brew#

$ brew install libevent
$ sudo pip install gevent

Port#

$ sudo port install libevent
$ CFLAGS="-I /opt/local/include -L /opt/local/lib" pip install gevent