code: def add_update_users(self, users, capacity=None):
          # type: (List[Union[hdx.data.user.User,Dict,str]],Optional[str]) -> None
          
          if not isinstance(users, list):
              raise HDXError('Users should be a list!')
          for user in users:
              self.add_update_user(user, capacity)
docs: Add new or update existing users in organization with new metadata. Capacity eg. member, admin
          must be supplied either within the User object or dictionary or using the capacity argument (which takes
          precedence).
  
          Args:
              users (List[Union[User,Dict,str]]): A list of either user ids or users metadata from User objects or dictionaries
              capacity (Optional[str]): Capacity of users eg. member, admin. Defaults to None.
  
          Returns:
              None