# ...

function parse_git_branch {
  ref=$(git symbolic-ref HEAD 2> /dev/null) || return
  echo -e " \e[0;33m"\(${ref#refs/heads/}\)
}

if [ "$color_prompt" = yes ]; then
    PS1="\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\$(parse_git_branch)\[\033[00m\]\$ "
else
    PS1='\u@\h:\w\$ '
fi
unset color_prompt force_color_prompt

# ...