Git branch in prompt

gistfile1.sh

function parse_git_branch {
  ref=$(git symbolic-ref HEAD 2> /dev/null) || return
  echo "("${ref#refs/heads/}") "
}

green='\[\e[32;1m\]'
blue='\[\e[34;1m\]'
red='\[\e[31;1m\]'
nocolour='\[\e[0m\]'
user="\u"

export PS1="$green$user $red\W $blue\$(parse_git_branch)$nocolour\$ "