Use pydantic ValidationError("msg") as a variable

Question

I want to use pydantic as a variable, for example to do this:

bla = ValidationError("msg")

but I get

pydantic.error_wrappers.ValidationError.__init__
TypeError: __init__() takes exactly 3 positional arguments (2 given)

while I see many that uses ValidationError("msg") when using it in a raise context

ultimatly i'm trying to use it in a parametize test like so:

@pytest.mark.parametrize("exception_side_effect, expected_exception, error_message", [
    (ProgrammingError("exceeded for unload single file mode."), PeachBaseServiceException, "Too much data fetched for a single file"),
    (ValidationError("unexpected error while trying to execute query"), ValidationError, "error loading query results to"),
    (Exception("unexpected error while trying to execute query"), Exception, "unexpected error")
])
def test_error_raised(
        exception_side_effect: Exception,
        expected_exception: Type[Exception],
        error_message: str
):

but for some reason i can't write ValidationError("msg") this way