func (s *FileSequence) SetExt(ext string) {
	if !strings.HasPrefix(ext, ".") {
		ext = "." + ext
	}
	s.ext = ext
}
func (s *FileSequence) SetExt(ext string) {
	if !strings.HasPrefix(ext, ".") {
		ext = "." + ext
	}
	s.ext = ext
}
func ( s * FileSequence ) SetExt ( ext string ) { if ! strings . HasPrefix ( ext , " " ) { ext = " " + ext } s . ext = ext }
// Set a new ext for the sequence
Set a new ext for the sequence