docs: def generate(self, url, browsers=None, orientation=None, mac_res=None, win_res=None,
                               quality=None, local=None, wait_time=None, callback_url=None):
          """
          Generates screenshots for a URL.
          """
          if isinstance(browsers, dict):
              browsers = [browsers]
          if browsers is None:
              browsers = [self.default_browser]
          data = dict((key, value) for key, value in locals().items() if value is not None and key != 'self')
          return self.execute('POST', '/screenshots', json=data)