code: def validate_api_key(self):
      url = f"{self.luma_base_endpoint}public/v1/user/get-self"
      content = self.make_request(url)
      if content["code"] != 200:
          raise Exception(
              "User Authentication failed - "
              + json.dumps(content["content"])
          )
      return content
  
file_path: mindsdb/mindsdb/integrations/handlers/luma_handler/luma.py
imports: import json
  import requests
label_desc: Use image node_id 3 for calling the LumaClient obj's underlying member method code with example usage: obj.validate_api_key() and returns: content