code: def test_file():
      with tempfile.NamedTemporaryFile() as tmp:
          # Existing files pass validation.
          assert us.File.validate(tmp.name) == tmp.name
  
      # random paths that I made up dont!
      with pytest.raises(s.SchemaError):
          assert us.File.validate("random")
  
imports: import tempfile
  import schema
  import caliban.util.schema
  import pytest
label_desc: Use image node_id 2 for calling a global function with example usage: test_file() without return types