title: unexpected argument 'eval_metric' in Xgboost
body: <p>I tried to use the eval_metric argument in XgBoost but got this error:</p>
  
  <blockquote>
    <p>TypeError: fit() got an unexpected keyword argument 'eval_metric'</p>
  </blockquote>
  
  <p>Here is my code:</p>
  
  <pre><code>eval_set = [(X_test_np, y_test_np)]
  model = XGBClassifier()
  model.fit(X_train_np, y_train_np,eval_metric="auc", eval_set=eval_set)
  </code></pre>
  
  <p>Does anyone know the solution to this problem?</p>