code: def test_size_palette():
      with pytest.warns(PlotnineWarning):
          # Warns against a discrete size scale
          s = scale_size_discrete()
          items = s.palette(9)
          assert len(items) == 9
  
      s = scale_size_continuous(range=(1, 6))
      frac = 0.5
      value = s.palette(frac**2)
      assert value == (1 + 6) * frac
  
      # Just test that they work
      s = scale_size_area(max_size=6)
      s.palette(frac**2)
  
      s = scale_size_radius(range=(1, 6))
      s.palette(frac**2)
  
imports: import warnings
  from datetime import datetime
  import numpy
  import numpy.testing
  import pandas
  import pytest
  import plotnine
  from plotnine import aes, annotate, element_text, expand_limits, facet_wrap, geom_bar, geom_col, geom_point, ggplot, lims, theme
  from plotnine.exceptions import PlotnineError, PlotnineWarning
  from plotnine.scales import scale_color, scale_color_manual, scale_identity, scale_manual, scale_xy
  from plotnine.scales.scale_alpha import scale_alpha_continuous, scale_alpha_discrete
  from plotnine.scales.scale_linetype import scale_linetype_continuous, scale_linetype_discrete
  from plotnine.scales.scale_manual import _scale_manual
  from plotnine.scales.scale_shape import scale_shape_continuous, scale_shape_discrete
  from plotnine.scales.scale_size import scale_size_area, scale_size_continuous, scale_size_discrete, scale_size_radius
  from plotnine.scales.scale_xy import scale_x_continuous, scale_x_discrete, scale_x_log10, scale_y_continuous
  from plotnine.scales.scales import make_scale
label_desc: Use image node_id 7 for calling a global function with example usage: test_size_palette() without return types