import unittest
import re
import nltk
from nltk.tokenize import word_tokenize
from nltk.corpus import stopwords
from nltk.stem import PorterStemmer


# Helper functions
def _require_success(test_case, condition, failure_message):
    if not condition:
        test_case._testMethodName = failure_message
        test_case.fail()

def _check_success(test_case, condition, success_message, failure_message):
    if condition:
        test_case._testMethodName = success_message
    else:
        test_case._testMethodName = failure_message
        test_case.fail()


class TestUserCode(unittest.TestCase):
    # Test that everything is imported correctly
    def test_imports(self):
        import user_code
        _require_success(
            self, 
            hasattr(user_code, "word_tokenize"), 
            "`word_tokenize` is not declared"
        )
        _require_success(
            self,
            user_code.word_tokenize == word_tokenize,
            "`word_tokenize` is declared, but it's not `nltk.tokenize.word_tokenize`"
        )
        _require_success(
            self, 
            hasattr(user_code, "stopwords"), 
            "`stopwords` is not declared"
        )
        _require_success(
            self,
            user_code.stopwords == stopwords,
            "`stopwords` is declared, but it's not `nltk.corpus.stopwords`"
        )
        _require_success(
            self, 
            hasattr(user_code, "PorterStemmer"), 
            "`PorterStemmer` is not declared"
        )
        _require_success(
            self,
            user_code.PorterStemmer == PorterStemmer,
            "`PorterStemmer` is declared, but it's not `nltk.stem.PorterStemmer`"
        )
        _require_success(
            self,
            hasattr(user_code, "nltk"),
            "`nltk` is not declared"
        )
        _require_success(
            self,
            user_code.nltk == nltk,
            "`nltk` is declared, but it's not `nltk` library"
        )
        self._testMethodName = "imports are correct"

    # Test that required NLTK resources are downloaded
    def test_nltk_downloads(self):
        import user_code
        _require_success(
            self,
            hasattr(user_code, "nltk"),
            "`nltk` is not declared"
        )
        _require_success(
            self,
            user_code.nltk == nltk,
            "`nltk` is declared, but it's not `nltk` library"
        )
        with open("user_code.py", "r") as f:
            user_code_text = f.read()
            _require_success(
                self,
                re.search(r"nltk *\. *download *\( *'punkt_tab' *\)", user_code_text),
                "Code for downloading `'punkt_tab'` tokenizer shouldn't be modified"
            )
            _require_success(
                self,
                re.search(r"nltk *\. *download *\( *'stopwords' *\)", user_code_text),
                "Code for downloading `'stopwords'` shouldn't be modified"
            )
        self._testMethodName = "NLTK resources are downloaded"

    # Test original text
    def test_text(self):
        import user_code
        expected = "Despite the pouring rain, the overwhelming sense of joy and accomplishment made the day unforgettable!"
        _require_success(
            self, 
            hasattr(user_code, "text"), 
            "`text` is not declared"
        )
        _check_success(
            self,
            user_code.text == expected,
            "`text` contains correct value",
            "`text` shouldn't be modified"
        )

    # Test lowercase conversion
    def test_text_lower(self):
        import user_code
        _require_success(
            self, 
            hasattr(user_code, "text"), 
            "`text` is not declared"
        )
        _require_success(
            self, 
            isinstance(user_code.text, str), 
            "`text` is not a string"
        )
        _require_success(
            self, 
            hasattr(user_code, "text_lower"), 
            "`text_lower` is not declared"
        )
        _check_success(
            self,
            user_code.text_lower == user_code.text.lower(),
            "`text_lower` is computed correctly",
            "`text_lower` is not the lowercase of `text`"
        )

    # Test tokenization of text_lower
    def test_tokens(self):
        import user_code
        _require_success(
            self, 
            hasattr(user_code, "text_lower"), 
            "`text_lower` is not declared"
        )
        _require_success(
            self, 
            isinstance(user_code.text_lower, str), 
            "`text_lower` is not a string"
        )
        _require_success(
            self, 
            hasattr(user_code, "tokens"), 
            "`tokens` is not declared"
        )
        _check_success(
            self,
            user_code.tokens == word_tokenize(user_code.text_lower),
            "`tokens` is computed correctly",
            "`text_lower` is not correctly tokenized into words"
        )

    # Test stop_words set
    def test_stop_words(self):
        import user_code
        _require_success(
            self, 
            hasattr(user_code, "stop_words"), 
            "`stop_words` is not declared"
        )
        _require_success(
            self, 
            isinstance(user_code.stop_words, set), 
            "`stop_words` is not a set"
        )
        _check_success(
            self,
            user_code.stop_words == set(stopwords.words('english')),
            "`stop_words` contains correct English stopwords set",
            "`stop_words` doesn't contain English stopwords"
        )

    # Test filtered_tokens filtering
    def test_filtered_tokens(self):
        import user_code
        _require_success(
            self, 
            hasattr(user_code, "tokens"), 
            "`tokens` is not declared"
        )
        _require_success(
            self, 
            isinstance(user_code.tokens, list), 
            "`tokens` is not a list"
        )
        _require_success(
            self, 
            hasattr(user_code, "stop_words"), 
            "`stop_words` is not declared"
        )
        _require_success(
            self, 
            isinstance(user_code.stop_words, set), 
            "`stop_words` is not a set"
        )
        _require_success(
            self, 
            hasattr(user_code, "filtered_tokens"), 
            "`filtered_tokens` is not declared"
        )
        expected = [tok for tok in user_code.tokens if tok not in user_code.stop_words]
        _check_success(
            self,
            user_code.filtered_tokens == expected,
            "`filtered_tokens` is computed correctly",
            "stop words in `tokens` are not correctly filtered out"
        )

    # Test stemmer instance
    def test_stemmer(self):
        import user_code
        _require_success(
            self, 
            hasattr(user_code, "stemmer"), 
            "`stemmer` is not declared"
        )
        _check_success(
            self,
            isinstance(user_code.stemmer, PorterStemmer),
            "`stemmer` is defined correctly",
            "`stemmer` is not an instance of `PorterStemmer`"
        )

    # Test stemming results
    def test_stemmed_tokens(self):
        import user_code
        _require_success(
            self, 
            hasattr(user_code, "stemmer"), 
            "`stemmer` is not declared"
        )
        _require_success(
            self,
            isinstance(user_code.stemmer, PorterStemmer),
            "`stemmer` is not an instance of `PorterStemmer`"
        )
        _require_success(
            self, 
            hasattr(user_code, "filtered_tokens"), 
            "`filtered_tokens` is not declared"
        )
        _require_success(
            self, 
            isinstance(user_code.filtered_tokens, list), 
            "`filtered_tokens` is not a list"
        )
        _require_success(
            self, 
            hasattr(user_code, "stemmed_tokens"), 
            "`stemmed_tokens` is not declared"
        )
        expected = [user_code.stemmer.stem(tok) for tok in user_code.filtered_tokens]
        _check_success(
            self,
            user_code.stemmed_tokens == expected,
            "`stemmed_tokens` is computed correctly",
            "`filtered_tokens` are not correctly stemmed"
        )

    # Test print statement
    def test_print(self):
        with open("user_code.py", "r") as f:
            user_code_text = f.read()
        _check_success(
            self,
            re.search(r"print *\( *\\"Stemmed tokens:\\" *, *stemmed_tokens *\)", user_code_text),
            "print statement is correct",
            "print statement shouldn't be modified"
        )


if __name__ == '__main__':
    nltk.download('punkt_tab')
    nltk.download('stopwords')
    unittest.main()

test_main.py

Utforska grunderna i Natural Language Processing (NLP) genom att lära dig viktiga tekniker för textförbehandling och metoder för att representera textdata. Få praktisk erfarenhet av verktyg som används för att rensa, analysera och tolka textuell information. Utveckla färdigheter för att omvandla rå språkdata till strukturerade insikter och skapa en stabil grund för avancerade tillämpningar inom artificiell intelligens och maskininlärning.

Fördjupa dig i grunderna för textförbehandling för att förbereda råtext för analys. Lär dig hur man tokeniserar text, filtrerar bort stoppord och anpassar tokenisering med reguljära uttryck.

Utforska hur ord kan reduceras till sina grundformer med hjälp av stamning och lemmatisering. Behärska ordklassmärkning för att berika text med grammatisk kontext och tillämpa ordklassmedveten lemmatisering.

Lär dig hur text kan representeras med siffror genom vektorrumsmodeller. Få praktisk erfarenhet genom att implementera och anpassa två populära vektorrumsmodeller: bag of words och TF-IDF.

Få en gedigen förståelse för ordembeddingar och hur de fångar semantisk betydelse. Utforska CBoW- och Skip-gram-arkitekturer som används i Word2Vec, samt implementera dem själv.

Utmaning: Stemming

Lösning

Awesome!

Utmaning: Stemming

Lösning