post-checkout hook for python pyc files on git. See http://stackoverflow.com/questions/1504724/a-git-hook-for-whenever-i-change-branches and http://codeinthehole.com/writing/a-useful-git-post-checkout-hook-for-python-repos/

post-checkout

#!/usr/bin/env bash

# gist at https://gist.github.com/miebach/7391024

# save this file to .git/hooks/post-checkout 
# and also to .git/hooks/post-merge
# and make it executable

# Delete .pyc files and empty directories from root of project
cd ./$(git rev-parse --show-cdup)

# Clean-up
find . -name ".DS_Store" -type f | xargs rm -f

NUM_PYC_FILES=$( find . -name "*.pyc" -type f | wc -l | tr -d ' ' )
if [ $NUM_PYC_FILES -gt 0 ]; then
    find . -name "*.pyc" -type f | xargs rm -f
    printf "\e[00;31mDeleted $NUM_PYC_FILES .pyc files\e[00m\n"
fi

NUM_EMPTY_DIRS=$( find . -type d -empty | wc -l | tr -d ' ' )
if [ $NUM_EMPTY_DIRS -gt 0 ]; then
    find . -type d -empty -type f | xargs rm -f
    printf "\e[00;31mDeleted $NUM_EMPTY_DIRS empty directories\e[00m\n"
fi