I used tweepy, textblob and plotly to chart the positive/ negative sentiments in the tweets. The results are here -
https://plot.ly/~ashane/4/gaps/ --> Barack Obama
https://plot.ly/~ashane/2/gaps/ --> Donald Trump
https://plot.ly/~ashane/6/gaps/ --> Narendra Modi
Modi makes the fewest negative sentiment tweets, Trump the most. Trump also makes the most positive sentiment tweets. Obama stays mostly in the middle. Interestingly there is a point after which his tweets are mostly positive sentiment. It could correlate to the time after he left office.
The code for this is https://github.com/thcricketfan/PythonAnalysis
Comments/interpretations and suggestions are welcome.