code: def test_update_missing_error():
      x0 = float64("x0")
      const = float64("const")
      with pytest.raises(
          ValueError,
          match="An update must be given for each init variable",
      ):
          ScalarLoop(init=[x0], constant=[const], update=[])
  
imports: import re
  import numpy
  import pytest
  from pytensor import Mode, function
  from pytensor.scalar import Composite, as_scalar, cos, exp, float16, float32, float64, identity, int64, sin
  from pytensor.scalar.loop import ScalarLoop
  from pytensor.tensor import exp
label_desc: Use image node_id 5 for calling a global function with example usage: test_update_missing_error() without return types