def populate_pydantic_default_values(attrs: Dict) -> Tuple[Dict, Dict]:
    """
    Extracts ormar fields from annotations (deprecated) and from namespace
    dictionary of the class. Fields declared on model are all subclasses of the
    BaseField class.

    Trigger conversion of ormar field into pydantic FieldInfo, which has all needed
    parameters saved.

    Overwrites the annotations of ormar fields to corresponding types declared on
    ormar fields (constructed dynamically for relations).
    Those annotations are later used by pydantic to construct it's own fields.

    :param attrs: current class namespace
    :type attrs: Dict
    :return: namespace of the class updated, dict of extracted model_fields
    :rtype: Tuple[Dict, Dict]
    """
    model_fields = {}
    potential_fields = {}

    potential_fields.update(get_potential_fields(attrs))
    for field_name, field in potential_fields.items():
        field.name = field_name
        model_fields[field_name] = field
        default_type = (
            field.__type__ if not field.nullable else Optional[field.__type__]
        )
        overwrite_type = (
            field.__pydantic_type__
            if field.__type__ != field.__pydantic_type__
            else None
        )
        attrs["__annotations__"][field_name] = overwrite_type or default_type
    return attrs, model_fields

    Extracts ormar fields from annotations (deprecated) and from namespace
    dictionary of the class. Fields declared on model are all subclasses of the
    BaseField class.

    Trigger conversion of ormar field into pydantic FieldInfo, which has all needed
    parameters saved.

    Overwrites the annotations of ormar fields to corresponding types declared on
    ormar fields (constructed dynamically for relations).
    Those annotations are later used by pydantic to construct it's own fields.

    :param attrs: current class namespace
    :type attrs: Dict
    :return: namespace of the class updated, dict of extracted model_fields
    :rtype: Tuple[Dict, Dict]
    
ormar/models/helpers/pydantic.py