config.extConfiguration = new ExtConfiguration(config);
ExtInstantiation ins = new ExtInstantiation("com.example.Bean");
ins.importList.add("com.example.BeanFactory");
ins.assignCode = "BeanFactory.getInstance();";
config.extConfiguration.extInstantiations.add(ins);
TestMethodMeta testMethodMeta = new TestMethodMeta();
testMethodMeta.classMeta = new ClassMeta();
testMethodMeta.classMeta.name = "Bean";
testMethodMeta.classMeta.importedList.add("com.example.Bean");
testMethodMeta.classMeta.packageName = "com.example";
String actual = GeneratorImplFunction.getInstantiationSourceCode(config, appender, testMethodMeta);