[Python] Python pydantic xml with TypeVar and Generic Type model is partially initialized

I'm new to python and I'm tasked in building a fastapi service that returns an xml format of a model/class in python. I'm using pydantic_xml with TypeVar and Generic but keep getting the error 'model is partially initialized'

>>> from pydantic_xml import BaseXmlModel, element
>>>
>>> from typing import TypeVar, Generic
>>>
>>> T = TypeVar('T')
>>>
>>> class Data(BaseXmlModel, Generic[T]):
...
... data:T = element(tag='data')
...
>>>
>>> class Result(BaseXmlModel):
...
... total: int = element(default = 0)
... data: Data = element(default = None)
...
>>>
>>> data = Data(data = [1,2,3,4])
>>> result = Result(total = 0, data = data)
>>>
>>> print(result.to_xml())
Traceback (most recent call last):
File "<python-input-166>", line 1, in <module>
print(result.to_xml())
~~~~~~~~~~~~~^^
File "/Users/las/Projects/ds-hcm/rip-service-hcm-recruitment/.venv/lib/python3.13/site-packages/pydantic_xml/model.py", line 604, in to_xml
self.to_xml_tree(skip_empty=skip_empty, exclude_none=exclude_none, exclude_unset=exclude_unset),
~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Users/ads/Projects/ds-hcm/rip-service-hcm-recruitment/.venv/lib/python3.13/site-packages/pydantic_xml/model.py", line 577, in to_xml_tree
self.__xml_serializer__.serialize(
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
root, self, pdc.to_jsonable_python(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
...<6 lines>...
exclude_unset=exclude_unset,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
)
^
File "/Users/ads/Projects/ds-hcm/rip-service-hcm-recruitment/.venv/lib/python3.13/site-packages/pydantic_xml/serializers/factories/model.py", line 179, in serialize
field_serializer.serialize(
~~~~~~~~~~~~~~~~~~~~~~~~~~^
element, getattr(value, field_name), encoded[field_name],
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
...<2 lines>...
exclude_unset=exclude_unset,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
)
^
File "/Users/ads/Projects/ds-hcm/rip-service-hcm-recruitment/.venv/lib/python3.13/site-packages/pydantic_xml/serializers/factories/model.py", line 394, in serialize
assert self._model.__xml_serializer__ is not None, f"model {self._model.__name__} is partially initialized"
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AssertionError: model Data is partially initialized


I have read the this discussion but can't seem to understand how to implement it.

Appreciate any help.

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