add and remove pip install/uninstall from requirements.txt automatically

.bashrc

# add pip install/uninstall to requirements.txt automatically
pipr() {
 if [ "$1" == "install" ]; then
    pip $1 $2
    pip freeze | grep -i $2 >> requirements.txt
    echo ok, added $2 as:
    tail -n1 requirements.txt
 fi
 if [ "$1" == "uninstall" ]; then
    echo y | pip $1 $2 >> .pipremoved
    grep -i "successfully uninstalled" .pipremoved | grep -o -i $2 >> requirements.removed
    cp requirements.txt requirements.bak
    tail -n1 requirements.removed | xargs -I{}  grep -v {} requirements.bak > requirements.txt
    echo ok, removed:
    tail -n1 requirements.removed
    rm .pipremoved >/dev/nul
 fi
}

Some more links :

http://stackoverflow.com/questions/20006000/install-a-package-and-write-to-requirements-txt-with-pip

http://codeinthehole.com/writing/using-pip-and-requirementstxt-to-install-from-the-head-of-a-github-branch/

pip freeze > requirements.txt

pip freeze | sed 's/@[a-z0-9]\+//' > requirements.txt