code: def test_invalid_scalar():
      s = pc.cast(pa.scalar(b"\xff"), pa.string(), safe=False)
      s.validate()
      with pytest.raises(
          ValueError, match="string scalar contains invalid UTF8 data"
      ):
          s.validate(full=True)
  
imports: import datetime
  import decimal
  import pytest
  import sys
  import weakref
  import numpy
  import pyarrow
  import pyarrow.compute
  from pyarrow.tests import util
label_desc: Use image node_id 2 for calling a global function with example usage: test_invalid_scalar() without return types