code: function formatAttrs(attributes, opts, keyOnlyAttribs = []) {
    if (!attributes) return;
  
    var output = '',
      value;
  
    // Loop through the attributes
    for (var key in attributes) {
      value = attributes[key];
      if (output) {
        output += ' ';
      }
  
      if (!value && booleanAttributes[key] || isExpr(key) || isKeyOnlyAttr(key, keyOnlyAttribs)) {
        output += key;
      } else {
        output += key + `=${isExpr(value) ? '' : '"'}` + (opts.decodeEntities ? entities.encodeXML(value) : value) + (isExpr(value) ? '' : '"');
      }
    }
  
    return output;
  }
docs: /*
  Format attributes