[Python] automatically add fields_validators based on hint type with pydantic

I'd like to define once for all fields_validators function in a BaseModel class, and inherit this class in my model, and the validators should apply to the updated class attributes.

MWE

def to_int(v: Union[str, int]) -> int:
if isinstance(v, str):
if v.startswith("0x"):
return int(v, 16)
return int(v)
return v


def to_bytes(v: Union[str, bytes, list[int]]) -> bytes:
if isinstance(v, bytes):
return v
elif isinstance(v, str):
if v.startswith("0x"):
return bytes.fromhex(v[2:])
return v.encode()
else:
return bytes(v)


class BaseModelCamelCase(BaseModel):
model_config = ConfigDict(
populate_by_name=True,
alias_generator=AliasGenerator(
validation_alias=lambda name: AliasChoices(to_camel(name), name)
),
)

# FIXME: should apply to int type from get_type_hints only
@field_validator("*", mode="before")
def to_int(cls, v: Union[str, int]) -> int:
return to_int(v)

# FIXME: should apply to bytes type from get_type_hints only
@field_validator("*", mode="before")
def to_bytes(cls, v: Union[str, bytes, list[int]]) -> bytes:
return to_bytes(v)

class BaseTransactionModel(BaseModelCamelCase):
nonce: int
gas: int = Field(validation_alias=AliasChoices("gasLimit", "gas_limit", "gas"))
to: Optional[bytes]
value: int
data: bytes
r: int = 0
s: int = 0



I tried to use model_validate but then I lost the alias parsing

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