code: def test_copy_command():
      multiline = b.copy_command(
          1,
          1,
          "face",
          "cake",
          "This is an example\nof a multiline comment.",
      )
  
      assert (
          multiline
          == f"""# This is an example
  # of a multiline comment.
  COPY --chown=1:1 face cake
  """
      )
  
      # single lines don't append comments.
      oneline = b.copy_command(1, 1, "face", "cake.py")
      assert (
          oneline
          == """COPY --chown=1:1 face cake.py
  """
      )
  
      # single comments work.
      oneline_comment = b.copy_command(
          1, 1, "face", "cake.py", comment="Comment!"
      )
      assert (
          oneline_comment
          == f"""# Comment!
  COPY --chown=1:1 face cake.py
  """
      )
  
label_desc: Use image node_id 2 for calling a global function with example usage: test_copy_command() without return types