from random import choice
from nltk.tokenize import sent_tokenize, word_tokenize

with open("dixit.txt") as article:
    quotes = sent_tokenize(article.read())

text_in = ""
while text_in != "stop":
    text_in = input("> ")
    text_out = "> "
    words_in = word_tokenize(text_in)
    words_in.sort(key = lambda s: len(s)).reverse()
    quote_found = False
    for word in words_in:
        for quote in quotes:
            if word in quote:
                text_out += "À propos de %s, Einstein a dit un jour : \"%s\"." % (word, quote)
                quote_found = True
                break
        if quote_found:
            break
    print(choice(quotes));