def validate_config(self, config):
<EOL>if not config:<EOL><INDENT>return config<EOL><DEDENT>spec = validate_experiment_spec_config(config)<EOL>if spec.is_experiment:<EOL><INDENT>return config<EOL><DEDENT>raise ValidationError('<STR_LIT>'<EOL>'<STR_LIT>'<EOL>'<STR_LIT>'.format(spec.kind))<EOL>
We only validate the config if passed.

        Also we use the ExperimentSpecification to check if this config was
        intended as an experiment.