code: def test_bar_color_raises(df):
      msg = "`color` must be string or list or tuple of 2 strings"
      with pytest.raises(ValueError, match=msg):
          df.style.bar(color={"a", "b"}).to_html()
      with pytest.raises(ValueError, match=msg):
          df.style.bar(color=["a", "b", "c"]).to_html()
  
      msg = "`color` and `cmap` cannot both be given"
      with pytest.raises(ValueError, match=msg):
          df.style.bar(
              color="something", cmap="something else"
          ).to_html()
  
imports: import gc
  import numpy
  import pytest
  from pandas import DataFrame, IndexSlice, Series
  import matplotlib
  from pandas.io.formats.style import Styler
label_desc: Use image node_id 20 for calling a global function with example usage: test_bar_color_raises(df) without return types