code: def test_not_tarining_data_to_plot(self):
      optimizer = algorithms.Adadelta(self.network)
  
      with warnings.catch_warnings(record=True) as warns:
          optimizer.plot_errors()
          self.assertEqual(1, len(warns))
          self.assertEqual(
              str(warns[-1].message), "There is no data to plot"
          )
  
file_path: neupy/tests/algorithms/test_plots.py
imports: import warnings
  import mock
  import pytest
  import matplotlib.pyplot
  from neupy import algorithms, layers
  from neupy.algorithms.plots import load_pandas_module
  from helpers import simple_classification
  from base import BaseTestCase
label_desc: Use image node_id 3 for calling the PlotsTestCase obj's underlying member method code with example usage: obj.test_not_tarining_data_to_plot() without return types