Binary package “python-nltk” in ubuntu xenial

Python libraries for natural language processing

 The Natural Language Toolkit (NLTK) is a leading platform for building
 Python programs to work with human language data. It provides easy-to-use
 interfaces to over 50 corpora and lexical resources such as WordNet,
 along with a suite of text processing libraries for classification,
 tokenization, stemming, tagging, parsing, and semantic reasoning.
 .
 This package contains the modules for Python2.