code: def test_plottype(self, close_figures):
      fig = interaction_plot(
          self.weight, self.duration, self.days, plottype="line"
      )
      assert_equal(isinstance(fig, plt.Figure), True)
      fig = interaction_plot(
          self.weight, self.duration, self.days, plottype="scatter"
      )
      assert_equal(isinstance(fig, plt.Figure), True)
      assert_raises(
          ValueError,
          interaction_plot,
          self.weight,
          self.duration,
          self.days,
          plottype="unknown",
      )
  
file_path: statsmodels/statsmodels/graphics/tests/test_factorplots.py
imports: import numpy
  from numpy.testing import assert_equal, assert_raises
  from pandas import Series
  import pytest
  from statsmodels.graphics.factorplots import _recode, interaction_plot
label_desc: Use image node_id 7 for calling the TestInteractionPlot obj's underlying member method code with example usage: obj.test_plottype(close_figures) without return types