input: from sklearn.naive_bayes import GaussianNB
  
  def train_naive_bayes_classifier(X_train, y_train, X_test):
      """Train a naive bayes classifier using GaussianNB and return the predictions on test data.
      >>> train_naive_bayes_classifier([[1, 2], [3, 4]], [0, 1], [[5, 6]])
      [1]
      """
      # Create a Gaussian Classifier
      model = GaussianNB()
      
      # Train the model using the training sets 
      model.fit(X_train, y_train)
      
      # Predict Output 
      y_pred = model.predict(X_test)
      return y_pred
output:     # Create a Gaussian Classifier
      model = GaussianNB()
      
      # Train the model using the training sets 
      model.fit(X_train, y_train)
      
      # Predict Output 
      y_pred = model.predict(X_test)
      return y_pred