code: def get_credentials(cmd_args):
          
          # Check the cmd args, return if we have something here
          cmd_credentials = cmd_args.email, cmd_args.key
          if cmd_credentials != (None, None):
              cli_logger.debug('Using command line configured credentials')
              return cmd_credentials
  
          env_email, env_api_key = get_config_from_env()
          if env_email is not None:
              if env_api_key is not None:
                  cli_logger.debug('Using environment configured credentials')
                  return env_email, env_api_key
  
          cfg_email, cfg_api_key = parse_config_file()
          if cfg_email is not None:
              if cfg_api_key is not None:
                  cli_logger.debug('Using .tagcube file configured credentials')
                  return cfg_email, cfg_api_key
  
          raise ValueError(NO_CREDENTIALS_ERROR)
docs: :return: The email and api_key to use to connect to TagCube. This
                   function will try to get the credentials from:
                      * Command line arguments
                      * Environment variables
                      * Configuration file
  
                   It will return the first match, in the order specified above.