Anyone know how to get a false positive pregnancy result?

Before y’all jump down my throat, my fiancé and I have quarantined all month in preparation for our friends Halloween party. The theme is reality tv iconic moments. Since we’re going as a couple, we decided to go as this couple from a show who had a very toxic relationship and not too long after they started she invited him out to a restaurant, sat down and pulled a pregnancy test out. We wanted to recreate that moment but I kinda want the test to say positive (perfectionism 🙄😬). Anyway I just thought it’s be cool if I could actually get the test to say positive.