Expanding url from shortened url obtained from tweet
Couple things I'd try:


switch to requests module reusing the requests.Session() to let it reuse the same TCP connection:


  ..if you're making several requests to the same host, the underlying TCP
  connection will be reused, which can result in a significant
  performance increase

use the "HEAD" HTTP method (in case of requests you may need the allow_redirects=True)
try out Scrapy web-scraping framework which is of an asynchronous nature and is based on the twisted network library. You would also move the CSV output part to an output pipeline.
another thing to try is use the grequests library (requests on gevent)


Some micro-optimization ideas:


move the hdr dictionary definition to the module level to avoid redefining it every time urlResolution() is called (and, since it is a constant use upper-case; and pick a more readable variable name - HEADERS?)