function theme
  {
      if [ -z "$1" ] || [ "$1" = "random" ]; then
  	themes=($ZSH/themes/*zsh-theme)
  	N=${#themes[@]}
  	((N=(RANDOM%N)+1))
  	RANDOM_THEME=${themes[$N]}
  	source "$RANDOM_THEME"
  	echo "[oh-my-zsh] Random theme '$RANDOM_THEME' loaded..."
      else
  	if [ -f "$ZSH_CUSTOM/$1.zsh-theme" ]
  	then
  	    source "$ZSH_CUSTOM/$1.zsh-theme"
  	else
  	    source "$ZSH/themes/$1.zsh-theme"
  	fi
      fi
  }
  
  function lstheme
  {
      cd $ZSH/themes
      ls *zsh-theme | sed 's,\.zsh-theme$,,'
  }