from sklearn.feature_extraction.text import CountVectorizer # create CountVectorizer object countvec = CountVectorizer() # create custom tokenizer function def my_tokenizer(text): return text.split() # set tokenizer function as parameter for CountVectorizer object countvec.set_params(tokenizer=my_tokenizer) # use CountVectorizer to fit and transform text data text_data = ["The quick brown fox", "jumps over the lazy dog"] count_matrix = countvec.fit_transform(text_data) # output tokenized text data and corresponding number matrix print(countvec.get_feature_names()) print(count_matrix.toarray())This example demonstrates how to create a custom tokenizer function and apply it to a text dataset using the CountVectorizer package. The output shows the tokenized text data and the corresponding numerical matrix. Package library: sklearn.feature_extraction.text