from nltk.stem import PorterStemmer
from nltk.stem import WordNetLemmatizer
from nltk.tokenize import word_tokenize
ps = PorterStemmer()
lemmatizer = WordNetLemmatizer()
tokenize_words = word_tokenize(sample_text)
stemmed_sample_text = []
for token in tokenize_words:
    stemmed_sample_text.append(ps.stem(token))
lemma_sample_text = []
for token in tokenize_words:
    lemma_sample_text.append(lemmatizer.lemmatize(token))
    
print ('\nOriginal Text:')
print ('------------------\n')
print (sample_text)
print ('\nFiltered Text: Stemming')
print ('------------------\n')
print (' '.join(str(token) for token in stemmed_sample_text))
print ('\nFiltered Text: Lemmatization')
print ('--------------------------------\n')
print (' '.join(str(token) for token in lemma_sample_text))