code: def test_html_mapping():
      d = dict(a=1, b=2)
      m = nbcollection.HTMLMapping(d, "some html string")
  
      assert list(m._ipython_key_completions_()) == ["a", "b"]
      assert list(m) == ["a", "b"]
      assert len(m) == 2
      assert m._repr_html_() == "some html string"
      assert dict(m) == d
  
imports: import pytest
  import pandas
  import numpy
  from sklearn_evaluation import NotebookCollection
  from sklearn_evaluation.nb import NotebookCollection
  from IPython.display import HTML
label_desc: Use image node_id 3 for calling a global function with example usage: test_html_mapping() without return types