code: def test_generalize_names():
      assert generalize_names("Samuel Eto'o") == "etoo s"
      assert generalize_names("Eto'o, Samuel") == "etoo s"
      assert generalize_names("Eto'o, Samuel") == "etoo s"
      assert generalize_names("Xavi") == "xavi"
      assert generalize_names("Yaya Toure") == "toure y"
      assert generalize_names("Pozo, Jose Angel") == "pozo j"
      assert generalize_names("Pozo, Jose Angel") == "pozo j"
      assert generalize_names("Jose Angel Pozo") == "pozo j"
      assert generalize_names("Jose Pozo") == "pozo j"
      assert (
          generalize_names(
              "Pozo, Jose Angel", firstname_output_letters=2
          )
          == "pozo jo"
      )
      assert (
          generalize_names("Eto'o, Samuel", firstname_output_letters=2)
          == "etoo sa"
      )
      assert (
          generalize_names("Eto'o, Samuel", firstname_output_letters=0)
          == "etoo"
      )
      assert (
          generalize_names("Eto'o, Samuel", output_sep=", ")
          == "etoo, s"
      )
      assert (
          generalize_names("Eto'o, Samuel", output_sep=", ")
          == "etoo, s"
      )
  
      assert (
          generalize_names("van Persie, Robin", output_sep=", ")
          == "vanpersie, r"
      )
      assert (
          generalize_names("Robin van Persie", output_sep=", ")
          == "vanpersie, r"
      )
      assert (
          generalize_names("Rafael van der Vaart", output_sep=", ")
          == "vandervaart, r"
      )
      assert (
          generalize_names("van der Vaart, Rafael", output_sep=", ")
          == "vandervaart, r"
      )
      assert generalize_names("Ben Hamer") == "hamer b"
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_generalize_names() without return types