NameError: name 'vectorizer' is not defined when using TfidfVectorizer

Hi I'm not sure what's wrong with my code. I've imported TfidfVectorizer, but it keeps saying 'Vectorizer' is not defined. Any help would be appreciated.

Here's my code:

from sklearn.feature_extraction.text import TfidfVectorizer


X = data_df.Title
X_tfidf = vectorizer.fit_transform(X)
y = data_df.Label

X_train, X_test, y_train, y_test = train_test_split(
    X_tfidf, y, test_size=0.33, random_state=42
)