code: def from_service_account_file(cls, filename, **kwargs):
          
          info, signer = _service_account_info.from_filename(
              filename, require=['client_email', 'token_uri'])
          return cls._from_signer_and_info(signer, info, **kwargs)
docs: Creates a Credentials instance from a service account json file.
  
          Args:
              filename (str): The path to the service account json file.
              kwargs: Additional arguments to pass to the constructor.
  
          Returns:
              google.auth.service_account.Credentials: The constructed
                  credentials.