code: func (po *Po) isValidLine(l string) bool {
  	// Check prefix
  	valid := []string{
  		"\"",
  		"msgctxt",
  		"msgid",
  		"msgid_plural",
  		"msgstr",
  	}
  
  	for _, v := range valid {
  		if strings.HasPrefix(l, v) {
  			return true
  		}
  	}
  
  	return false
  }
docs: // isValidLine checks for line prefixes to detect valid syntax.