from dmr import DMR

def test_validate_license_plate():
    """Test license plate validator"""
    is_license_plate = DMR().validate_license_plate("GGGGGGG")
    assert is_license_plate == True
    
    is_license_plate = DMR("GGGGGGG").validate_license_plate()
    assert is_license_plate == True
    
    is_license_plate = DMR().validate_license_plate("ThisIsNotReal")
    assert is_license_plate == False

def test_invalid_license_plate():
    dmr_obj = DMR().get_by_plate(license_plate="GGGGGGG")
    assert dmr_obj is None