'If the server requires special headers, such as a particular user agent
or a referrer, then implement this method in you plugin to return a
customized browser instance. See the Gutenberg plugin for an example.
Note that if you implement the open() method in your plugin and use the
WebStoreDialog class, remember to pass self.createbrowser in the
constructor of WebStoreDialog.'

def create_browser(self):

    raise NotImplementedError()
