Undefined names - Githubissues

flake8 testing of https://github.com/YouChouNoBB/sklearn-introduction on Python 3.6.3
$ flake8 . --count --select=E901,E999,F821,F822,F823 --show-source --statistics
./blending.py:28:36: F821 undefined name 'preprocess_train_input'
    train_x_id, train_x, train_y = preprocess_train_input()
                                   ^
./blending.py:29:30: F821 undefined name 'preprocess_val_input'
    val_x_id, val_x, val_y = preprocess_val_input()
                             ^
./ensemble.py:15:36: F821 undefined name 'train_test_split'
X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.1, random_state=111)
                                   ^
./ensemble.py:21:49: F821 undefined name 'RandomForestRegressor'
model_rf = Regressor(dataset=dataset, estimator=RandomForestRegressor, parameters={'n_estimators': 50},name='rf')
                                                ^
./ensemble.py:22:49: F821 undefined name 'LinearRegression'
model_lr = Regressor(dataset=dataset, estimator=LinearRegression, parameters={'normalize': True},name='lr')
                                                ^
./ensemble.py:30:49: F821 undefined name 'LinearRegression'
stacker = Regressor(dataset=stack_ds, estimator=LinearRegression)
                                                ^
./ensemble.py:33:40: F821 undefined name 'mean_absolute_error'
results = stacker.validate(k=10,scorer=mean_absolute_error)
                                       ^
./ensemble.py:42:36: F821 undefined name 'train_test_split'
X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.1, random_state=111)
                                   ^
./ensemble.py:48:49: F821 undefined name 'RandomForestRegressor'
model_rf = Regressor(dataset=dataset, estimator=RandomForestRegressor, parameters={'n_estimators': 50},name='rf')
                                                ^
./ensemble.py:49:49: F821 undefined name 'LinearRegression'
model_lr = Regressor(dataset=dataset, estimator=LinearRegression, parameters={'normalize': True},name='lr')
                                                ^
./ensemble.py:57:49: F821 undefined name 'LinearRegression'
stacker = Regressor(dataset=stack_ds, estimator=LinearRegression)
                                                ^
./ensemble.py:60:40: F821 undefined name 'mean_absolute_error'
results = stacker.validate(k=10,scorer=mean_absolute_error)
                                       ^
./ensemble.py:65:32: F821 undefined name 'boston_dataset'
dataset = Dataset(preprocessor=boston_dataset)
                               ^
./ensemble.py:67:49: F821 undefined name 'RandomForestRegressor'
model_rf = Regressor(dataset=dataset, estimator=RandomForestRegressor, parameters={'n_estimators': 151},name='rf')
                                                ^
./ensemble.py:68:49: F821 undefined name 'LinearRegression'
model_lr = Regressor(dataset=dataset, estimator=LinearRegression, parameters={'normalize': True},name='lr')
                                                ^
./ensemble.py:69:50: F821 undefined name 'KNeighborsRegressor'
model_knn = Regressor(dataset=dataset, estimator=KNeighborsRegressor, parameters={'n_neighbors': 15},name='knn')
                                                 ^
./ensemble.py:73:33: F821 undefined name 'mean_absolute_error'
weights = pipeline.find_weights(mean_absolute_error)
                                ^
17    F821 undefined name 'preprocess_train_input'
17
YouChouNoBB / data-mining-introduction

Undefined names #2
