You will use nltk to explore the Herman Melville novel Moby Dick. Write the python code for
answering the following questions:
Find how many tokens are unique after removing stopwords.
you can use follwing sample code
from nltk.corpus import stopwords
stop_words = set(stopwords.words('english'))
def example_three():
filtered_sentence = [w for w in raw if not w.lower() in stop_words]
filtered_sentence = []
for w in raw:
if w not in stop_words:
filtered_sentence.append(w)
return len(set(nltk.word_tokenize(filtered_sentence)))
example_three()