code: def columns_count(self):
      return 5
  
imports: import pytest
  from pandasai.connectors import BaseConnector
  from pandasai.connectors.base import BaseConnectorConfig
  from pandasai.helpers import Logger
label_desc: Use image node_id 6 for calling the MockConnector obj's underlying member method code with example usage: obj.columns_count() and returns: int