def _execute_verification(self):
tests = [test for test in self.tests if not isinstance(test, list)] +[individual_test for test in self.tests if isinstance(test, list) for individual_test in test]<EOL>for test in tests:<EOL><INDENT>if (test.result != constants.SKIPPED<EOL>and test.validation_function is not None<EOL>and (test.total_number_iterations <= <NUM_LIT:1>)<EOL>and not (runtime.get_active_config("<STR_LIT>",False))<EOL>and hasattr(test.validation_function, '<STR_LIT>')):<EOL><INDENT>try:<EOL><INDENT>test.validation_function()<EOL><DEDENT>except BaseException as e:<EOL><INDENT>test.result = constants.FAILED<EOL>test.exception = e<EOL><DEDENT><DEDENT><DEDENT>
Executes verification methods for the tests

:return: