'MLPRegressor' object has no attribute 'save'

This error occurs when you try to save a scikit-learn MLPRegressor model using the `save` method, which is not supported by this class.

To save a trained MLPRegressor model, you can use the `joblib` module from scikit-learn, which provides efficient persistence of Python objects. Here's an example:

from sklearn.neural_network import MLPRegressor
from sklearn.externals import joblib

# train MLPRegressor model
model = MLPRegressor(hidden_layer_sizes=(10, 5))
model.fit(X_train, y_train)

# save model
joblib.dump(model, 'mlp_model.pkl')

# load model
loaded_model = joblib.load('mlp_model.pkl')

# use model to make predictions
y_pred = loaded_model.predict(X_test)

In this example, we train an MLPRegressor model, save it to a file using `joblib.dump`, and then load it back into memory using `joblib.load`. We can then use the loaded model to make predictions on new data.