class_docstr: Knowledge base controller handles all
  manages knowledge bases
class_docstr_tok: ["Knowledge","base","controller","handles","all","manages","knowledge","bases"]
docstr: create a default embedding model for knowledge base, if not specified
docstr_tok: ["create","a","default","embedding","model","for","knowledge","base",",","if","not","specified"]
code: def _create_default_embedding_model(
      self, project_name, kb_name, engine="sentence_transformers"
  ):
      """create a default embedding model for knowledge base, if not specified"""
      model_name = f"{kb_name}_default_model"
  
      statement = CreatePredictor(
          name=Identifier(parts=[project_name, model_name]),
          using={},
          targets=[Identifier(parts=[TableField.CONTENT.value])],
      )
      ml_handler = self.session.integration_controller.get_handler(
          engine
      )
  
      self.session.model_controller.create_model(statement, ml_handler)
  
      return model_name
  
imports: import copy
  from typing import List
  import pandas
  import mindsdb_sql.planner.utils
  from mindsdb_sql.parser.ast import BinaryOperation, Constant, Identifier, Select, Update, Delete, Star
  from mindsdb_sql.parser.dialects.mindsdb import CreatePredictor
  import mindsdb.interfaces.storage.db
  from mindsdb.integrations.libs.vectordatabase_handler import TableField
  from mindsdb.utilities.exception import EntityExistsError, EntityNotExistsError
label_desc: Use image node_id 4 for calling the KnowledgeBaseController obj's underlying member method code with example usage: obj._create_default_embedding_model(project_name, kb_name, engine) and returns: model_name