[Python] Pydantic model fails with doctest on timestamp

that model may be pydantic correct

"""
This module defines the User model using Pydantic's BaseModel.

Example:
>>> user_model = UserModel(id=1, name='Alice')
>>> print(user_model)
id=1 name='Alice'
"""
from datetime import datetime
from pydantic import BaseModel, Field, field_validator

DATETIME_FORMAT = "%Y-%m-%dT%H:%M:%S.%f" # Format with microseconds

class UserModel(BaseModel):
"""User model representing a user with an id and name.

Attributes:
id (int): The unique identifier for the user.
name (str): The name of the user. Defaults to 'Jane Doe'.
timestamp (str): Timestamp of the event in the format
'%Y-%m-%dT%H:%M:%S.%f'. If None, the current time is used. Defaults
to None.

Example:
>>> user_model = UserModel(
... id=1,
... name='Alice'
... )
>>> user_model.model_dump_json()
'{"id":1,"name":"Alice","timestamp":"..."}'
"""
id: int
name: str = 'Jane Doe'
timestamp: str = Field(default_factory=lambda: datetime.now().strftime(DATETIME_FORMAT))

@field_validator("timestamp")
@classmethod
def check_datetime_format(cls, value: str) -> str:
"""Validates the format of the timestamp.

Ensures that the 'timestamp' value conforms to the defined DATETIME_FORMAT.

Args:
value: The timestamp string to validate.

Returns:
The validated timestamp string if the format is correct.

Raises:
ValueError: If the timestamp does not match the expected format.
"""
try:
datetime.strptime(value, DATETIME_FORMAT)
return value
except ValueError as exc:
raise ValueError(
f"The 'timestamp' field must have the format '{DATETIME_FORMAT}', received: '{value}'") from exc


but fails with doctest as the timestamp is always different in the output for doctest. Is there a way to have proper doctstring with timestamp output which works also for doctest ?

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