code: public static String getPremadeWidgetHtml(String guildId, WidgetTheme theme, int width, int height)
      {
          Checks.notNull(guildId, "GuildId");
          Checks.notNull(theme, "WidgetTheme");
          Checks.notNegative(width, "Width");
          Checks.notNegative(height, "Height");
          return String.format(WIDGET_HTML, guildId, theme.name().toLowerCase(), width, height);
      }
docs: Gets the pre-made HTML Widget for the specified guild using the specified
  settings. The widget will only display correctly if the guild in question
  has the Widget enabled. Additionally, this method can be used independently
  of being on the guild in question.
  
  @param  guildId
  the guild ID
  @param  theme
  the theme, light or dark
  @param  width
  the width of the widget
  @param  height
  the height of the widget
  
  @return a String containing the pre-made widget with the supplied settings