class_docstr: Test functionality of SkorchDoctor using a simple model
class_docstr_tok: ["Test","functionality","of","SkorchDoctor","using","a","simple","model"]
code: def test_plot_gradients_default(self, plt, doctor):
      axes = doctor.plot_gradients()
      assert isinstance(axes, np.ndarray)
      assert axes.shape == (1, 1)
      assert isinstance(axes[0, 0], plt.Subplot)
  
imports: import itertools
  from unittest import mock
  import numpy
  import pytest
  import torch
  from torch import nn
label_desc: Use image node_id 35 for calling the TestSkorchDoctorSimple obj's underlying member method code with example usage: obj.test_plot_gradients_default(plt, doctor) without return types