How to use get_best_lr method?

[amitjslearn]

How to use get_best_lr method from the class LRFinder
I tried

lr_finder.get_best_lr(sma=20)

I got the following error.

---------------------------------------------------------------------------
IndexError                                Traceback (most recent call last)
<ipython-input-28-407ca9d54a8d> in <module>
----> 1 lr_finder.get_best_lr(sma=20)

/kaggle/usr/lib/keras_lr_finder/keras_lr_finder.py in get_best_lr(self, sma, n_skip_beginning, n_skip_end)
    164     def get_best_lr(self, sma, n_skip_beginning=10, n_skip_end=5):
    165         derivatives = self.get_derivatives(sma)
--> 166         best_der_idx = np.argmax(derivatives[n_skip_beginning:-n_skip_end])[0]
    167         return self.lrs[n_skip_beginning:-n_skip_end][best_der_idx]

IndexError: invalid index to scalar variable.

[amitjslearn]

Does removing [0] from the this line best_der_idx = np.argmax(derivatives[n_skip_beginning:-n_skip_end])[0] from get_best_lr method work? I tried and I didn't get any errors. Will it still return the best learning rate?