Doubt on retrieving tweets for sentiment analysis?
First you need to setup the twitter api and get the credentials and add those to the congig.cfg file linked here- 
https://filebin.net/5a6lfserhqzjg93a/config.cfg?t=dcqh998i

Afterwards you can use this link https://filebin.net/nfeju0bjvh8tocl3/tweetering.py?t=dy6bk7x5 to download the tweets which contain Uber. 
Just run it on command line using - python tweetering.py Uber 

Hope it works for you. You can also find many links on medium.com where you can find the complete twitter sentiment analysis steps, reading which you will understand a lot of things.