async def test_run_async_1_missing_arg_async_func():
  """Test that run_async calls the function with 1 missing arg in signature (async function)."""
  tool = FunctionTool(async_function_for_testing_with_2_arg_and_no_tool_context)
  args = {"arg2": "test_value_1"}
  result = await tool.run_async(args=args, tool_context=MagicMock())
  assert result == {
      "error": """Invoking `async_function_for_testing_with_2_arg_and_no_tool_context()` failed as the following mandatory input parameters are not present:
arg1
You could retry calling this tool, but it is IMPORTANT for you to provide all the mandatory parameters."""
  }
Test that run_async calls the function with 1 missing arg in signature (async function).
tests/unittests/tools/test_function_tool.py