Непонятно, чего вы пытаетесь достичь, но этот код может решить вашу проблему.Приведенный ниже код содержит 3 вопроса, которые были набраны, токенизированы и нормализованы, удалены английские стоп-слова и обычные знаки препинания.
from nltk.corpus import stopwords
from nltk.tokenize import word_tokenize
# Import the string module needed to remove punctuation characters
from string import punctuation
# English stop words to remove from text.
# A stop word is a commonly used word, such
# as “the”, “a”, “an”, “in”
stop_words = set(stopwords.words('english'))
# ASCII characters which are considered punctuation characters.
# These characters will be removed from the text
exclude_punctuation = set(punctuation)
# Combine the stop words and the punctuations to remove
exclude_combined = set.union(stop_words, exclude_punctuation)
question_input = []
for i in range(3):
question_input.append(input("Please Enter Your Question: "))
# converts the question list into a group of strings that are separated by a comma
questions = (', '.join(question_input))
# Tokenize and normalized the questions
tokenize_input = word_tokenize(questions.lower().strip())
# Remove the English stop words and punctuations
expunge_stopwords_punctuations = [word for word in tokenize_input if not word in exclude_combined]
print (expunge_stopwords_punctuations)
sys.exit(0)
#####################################################
# INPUT
# Please Enter Your Question: This is a question.
# Please Enter Your Question: This is another question.
# Please Enter Your Question: This is the final question.
#####################################################
#####################################################
# OUTPUT
# ['question', 'another', 'question', 'final', 'question']
#####################################################