title: Reading back a saved LGBMClassifier model
body: <p>I trained a LGBMClassifier model and saved in a file in this way:</p>
  
  <pre><code>clf = lgb.LGBMClassifier( ... )
  clf.fit(X_train, y_train, **fit_params)
  clf.booster_.save_model("model1.txt")
  
  ##Predictions
  y_pred = clf.predict_proba(X_data, num_iteration=clf.best_iteration_)[:, 1]
  </code></pre>
  
  <p>Now what I want is to use the saved model for another prediction. But if I do this:</p>
  
  <pre><code>## new predictions:
  
      clf_fs = lgb.Booster(model_file='model1.txt')
      y_pred2 = clf_fs.predict_proba(X_data2, num_iteration=clf_fs.best_iteration_)[:, 1]
  </code></pre>
  
  <p>I got an error as</p>
  
  <pre><code>AttributeError: 'Booster' object has no attribute 'predict_proba'
  </code></pre>
  
  <p>I understand that <code>cls_fs</code> is an object of class <code>Booster</code> and not of a class <code>LGBMClassifier</code>, and that I can use <code>clf_fs.predict()</code>, but how I can get back a <code>LGBMClassifier</code> object from the saved booster file and all its specific attributes?</p>