small thing to change into synonyms the words of a text

synonyms.py

import thesaurus as th

wordlist = []
with open('test.txt') as f:
    wordlist = ([word for line in f for word in line.split()])

changedw = []
for word in wordlist:
    tmpword = th.Word(word).synonyms(relevance=3)
    if not tmpword:
        changedw.append(word)
    else:
        changedw.append(tmpword[0])

print(' '.join(changedw))