code: def get_item_type_id_from_identifier(self, identifier, item_types=None):
          
          if item_types is None:
              item_types = ItemType.objects.get_all_types()
          identifier_type, _ = identifier.split('/')
          item_types = [it for it in item_types.values() if it['table'].endswith(identifier_type)]
          if len(item_types) > 1:
              raise Exception('There is more than one item type for name "{}".'.format(identifier_type))
          if len(item_types) == 0:
              raise Exception('There is no item type for name "{}".'.format(identifier_type))
          return item_types[0]['id']
docs: Get an ID of item type for the given identifier. Identifier is a string of
          the following form:
  
          <model_prefix>/<model_identifier>
  
          where <model_prefix> is any suffix of database table of the given model
          which uniquely specifies the table, and <model_identifier> is
          identifier of the object.
  
          Args:
              identifier (str): item identifier
              item_types (dict): ID -> item type JSON
  
          Returns:
              int: ID of the corresponding item type