[Python] How to drop discriminator value from loc in validation error?

I use Pydantic v2. For now I'd like to remove discriminator value from loc or validation error. Please take a look at the code below:

from pprint import pprint
from typing import Literal, Union, Annotated, Any

from pydantic import BaseModel, Field, RootModel, ValidationError
from pydantic.main import Model


class Tiger(BaseModel):
animal_type: Literal["tiger"] = "tiger"
ferocity_scale: float = Field(..., ge=0, le=10)


class Shark(BaseModel):
animal_type: Literal["shark"] = "shark"
ferocity_scale: float = Field(..., ge=0, le=10)


class Lion(BaseModel):
animal_type: Literal["lion"] = "lion"
ferocity_scale: float


class WildAnimal(RootModel):
root: Annotated[Union[Tiger, Shark, Lion], Field(..., discriminator='animal_type')]


try:
my_shark = WildAnimal.model_validate({'animal_type': 'shark', 'ferocity_scale': 115})
except ValidationError as exc:
pprint(exc.errors())


The code prints:

[{'ctx': {'le': 10.0},
'input': 115,
'loc': ('shark', 'ferocity_scale'), <------ how to drop "shark"?
'msg': 'Input should be less than or equal to 10',
'type': 'less_than_equal',
'url': 'https://errors.pydantic.dev/2.7/v/less_than_equal'}]


In loc key you could notice ('shark', 'ferocity_scale'). The value shark is the discriminator animal_type value.

How to drop it by means of Pydantic? Or how to detect dynamically that the first value of loc is discriminator value?

The only thing I could figure out:

class WildAnimal(RootModel):
root: Annotated[Union[Tiger, Shark, Lion], Field(..., discriminator='animal_type')]

@classmethod
def model_validate(cls: type[Model], obj: Any, *, strict: bool | None = None, from_attributes: bool | None = None,
context: dict[str, Any] | None = None) -> Model:
try:
return super().model_validate(obj, strict=strict, from_attributes=from_attributes, context=context)
except ValidationError as exc:
# modify loc
# reraise ValidationError

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