code: func (h *Client) UserAgentOverride(userAgentOverride string) *Client {
  	h.userAgentOverride = userAgentOverride
  	h.userAgentOverrideSet = true
  	return h
  }
docs: // The User Agent of the browser. Note that Google has libraries
  // to identify real user agents. Hand crafting your own agent
  // could break at any time.