ValueError: TextPredictor should be a binary classifier for Precision Recall Curve

Question

I'm trying to plot a precision recall curve for binary text classification using ktrain (wrapper for BERT) and getting the following error

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-142-9069d96b6d6b> in <module>
----> 1 disp = plot_precision_recall_curve(predictor, df_testing.description.values, df_testing.pred_class)
      2 disp.ax_.set_title('2-class Precision-Recall curve: '
      3                    'AP={0:0.2f}'.format(average_precision))

C:\conda\lib\site-packages\sklearn\metrics\_plot\precision_recall_curve.py in plot_precision_recall_curve(estimator, X, y, sample_weight, response_method, name, ax, **kwargs)
    145         estimator.__class__.__name__))
    146     if not is_classifier(estimator):
--> 147         raise ValueError(classification_error)
    148 
    149     prediction_method = _check_classifer_response_method(estimator,

ValueError: TextPredictor should be a binary classifier

My predictor is <ktrain.text.predictor.TextPredictor at 0x2d9361e61c8>. Is there a way in which I can convert my predictor to a binary classifier?