I have no idea what that does. But consider debugging my removing tiny pieces of it one at a time until the problem goes away. That will identify the problem code. Then you can eitehr read up on that particular part of the
string or ask here.
export PS1="\e[37m\u@\h: \e[0;33m\W\$(parse_git_branch)\[\033[00m\]\e[37m$ "