code: func indentLines(str string, indent string) string {
  	if indent == "" {
  		return str
  	}
  
  	var indented []string
  
  	lines := strings.Split(str, "\n")
  	for i, line := range lines {
  		if (i == (len(lines) - 1)) && (line == "") {
  			// input string ends with a new line
  			indented = append(indented, line)
  		} else {
  			indented = append(indented, indent+line)
  		}
  	}
  
  	return strings.Join(indented, "\n")
  }
docs: // indentLines indents all lines of given string