code: func (p *WebPage) SendKeyboardEvent(eventType string, key string, modifier int) error {
  	return p.ref.process.doJSON("POST", "/webpage/SendKeyboardEvent", map[string]interface{}{"ref": p.ref.id, "eventType": eventType, "key": key, "modifier": modifier}, nil)
  }
docs: // SendKeyboardEvent sends a keyboard event as if it came from the user.
  // It is not a synthetic event.
  //
  // The eventType can be "keyup", "keypress", or "keydown".
  //
  // The key argument is a string or a key listed here:
  // https://github.com/ariya/phantomjs/commit/cab2635e66d74b7e665c44400b8b20a8f225153a
  //
  // Keyboard modifiers can be joined together using the bitwise OR operator.