Determine the valence intensity of the tweeter's mental state conveyed in the tweet "@DonaldJTrumpJr @realDonaldTrump Still say #RussiaProbe is #fakenews @DonaldJTrumpJr ? #ironic #lockhimup". Provide a score from 0 to 1, where 1 signifies very positive and 0 signifies very negative sentiment.