snowballstemmer package this python package will use the snowball' algorithm to extract the base form we can import this package with the help of the following python codefrom nltk stem snowball import snowballstemmer for exampleif we will give the word 'writingas the input to this stemmer then we will get the word 'writeafter stemming all of these algorithms have different level of strictness if we compare these three stemmers then the porter stemmers is the least strict and lancaster is the strictest snowball stemmer is good to use in terms of speed as well as strictness lemmatization we can also extract the base form of words by lemmatization it basically does this task with the use of vocabulary and morphological analysis of wordsnormally aiming to remove inflectional endings only this kind of base form of any word is called lemma the main difference between stemming and lemmatization is the use of vocabulary and morphological analysis of the words another difference is that stemming most commonly collapses derivationally related words whereas lemmatization commonly only collapses the different inflectional forms of lemma for exampleif we provide the word saw as the input word then stemming might return the word 'sbut lemmatization would attempt to return the word either see or saw depending on whether the use of the token was verb or noun in the python nltk modulewe have the following package related to lemmatization process which we can use to get the base forms of wordwordnetlemmatizer package this python package will extract the base form of the word depending upon whether it is used as noun or as verb we can import this package with the help of the following python codefrom nltk stem import wordnetlemmatizer chunkingdividing data into chunks it is one of the important processes in natural language processing the main job of chunking is to identify the parts of speech and short phrases like noun phrases we have already studied the process of tokenizationthe creation of tokens chunking basically is the labeling of those tokens in other wordschunking will show us the structure of the sentence in the following sectionwe will learn about the different types of chunking