possibility to display only names before ":" and hide everything behind it

I have a txt file with the following structure: Johan:6279f03c18e1665d451d93c66bd1eaad Annita:6279f03c18e1665d451d93c66bd1eaad Rudy:6279f03c18e1665d451d93c66bd1eaad Bert:ethrt74efgdg7jcnjsdnvfn53254 Gerdy:6279f03c18e1665d451d93c66bd1eaad Barbara:kfdnjkgnf34346353dfrferytyh Gil:6279f03c18e1665d451d93c66bd1eaad It contains username:password MD5hashed…