Resource u'tokenizers/punkt/english.pickle' not found

To add to alvas' answer, you can download only the punkt corpus:

nltk.download('punkt')

Downloading all sounds like overkill to me. Unless that's what you want.

If you're looking to only download the punkt model:

import nltk
nltk.download('punkt')

If you're unsure which data/model you need, you can install the popular datasets, models and taggers from NLTK:

import nltk
nltk.download('popular')

With the above command, there is no need to use the GUI to download the datasets.

I got the solution:

import nltk
nltk.download()

once the NLTK Downloader starts

Downloader> d

Download which package (l=list; x=cancel)? Identifier> punkt