Hello!
When attempting to run vaderSentiment after installing it in my venv with the suggested pip install vaderSentiment, I got the following error:

Traceback (most recent call last):
  File "rate.py", line 1, in <module>
    from vaderSentiment.vaderSentiment import SentimentIntensityAnalyzer
  File "/Users/martin/Documents/codingnomads/nlpython/big_projects/rate-mds/env/lib/python3.6/site-packages/vaderSentiment/vaderSentiment.py", line 17, in <module>
    import requests
ModuleNotFoundError: No module named 'requests'

Seems that requests is an implicit(?) dependency.
I looked for a requirements.txt but not sure that's how it works with packages up on PyPI.

My pip freeze suggests that a requirements.txt for vaderSentiment could look like this:

certifi==2018.4.16
chardet==3.0.4
idna==2.7
requests==2.19.1
urllib3==1.23

If this is helpful, I can create one and make a PR? But maybe there are other reasons for this not to be included that I am not aware of.

Let me know if this is something I can help with - would gladly do so :)