if err := DB.Create(&user).Error; err != nil {
		t.Fatalf("create user: %v", err)
	}

	if err := DB.Model(&user).Association("Languages").Append(map[string]interface{}{
		"code": "gm2m_map_1", "name": "GMap1",
	}); err != nil {
		t.Fatalf("append map: %v", err)
	}
	AssertAssociationCount(t, user, "Languages", 1, "after append 1 map (generic file)")

	// Append more maps individually