code: def create_link(self, token, folder_id, url, **kwargs):
          
          parameters = dict()
          parameters['token'] = token
          parameters['folderid'] = folder_id
          parameters['url'] = url
          optional_keys = ['item_name', 'length', 'checksum']
          for key in optional_keys:
              if key in kwargs:
                  if key == 'item_name':
                      parameters['itemname'] = kwargs[key]
                      continue
                  parameters[key] = kwargs[key]
          response = self.request('midas.link.create', parameters)
          return response
docs: Create a link bitstream.
  
          :param token: A valid token for the user in question.
          :type token: string
          :param folder_id: The id of the folder in which to create a new item
              that will contain the link. The new item will have the same name as
              the URL unless an item name is supplied.
          :type folder_id: int | long
          :param url: The URL of the link you will create, will be used as the
              name of the bitstream and of the item unless an item name is
              supplied.
          :type url: string
          :param item_name: (optional)  The name of the newly created item, if
              not supplied, the item will have the same name as the URL.
          :type item_name: string
          :param length: (optional) The length in bytes of the file to which the
              link points.
          :type length: int | long
          :param checksum: (optional) The MD5 checksum of the file to which the
              link points.
          :type checksum: string
          :returns: The item information of the item created.
          :rtype: dict