Hi there, I tried to use the method dict but i got an error: KeyError(__root__) Here an example:

1. Model structure:

from datetime import datetime, time
from typing import Optional, Union
from pydantic import Field, validator, BaseModel
from pydantic_collections import BaseCollectionModel

class OpeningTime(BaseModel):
    weekday: int = Field(..., alias="weekday")
    day: Optional[str] = Field(alias="day")  # NB: keep it after number_weekday attribute
    from_time: Optional[time] = Field(alias="fromTime")
    to_time: Optional[time] = Field(alias="toTime")

    @validator("day", pre=True)
    def generate_weekday(cls, weekday: str, values) -> str:
        if weekday is None or len(weekday) == 0:
            return WEEKDAYS[str(values["weekday"])]
        return weekday



class OpeningTimes(BaseCollectionModel[OpeningTime]):
    pass


class PaymentMethod(BaseModel):
    type: str = Field(..., alias="type")
    card_type: str = Field(..., alias="cardType")


class PaymentMethods(BaseCollectionModel[PaymentMethod]):
    pass


class FuelType(BaseModel):
    type: str = Field(..., alias="Fuel")


class FuelTypes(BaseCollectionModel[FuelType]):
    pass


class AdditionalInfoStation(BaseModel):
    opening_times: Optional[OpeningTimes] = Field(alias="openingTimes")
    car_wash_opening_times: Optional[OpeningTimes] = Field(alias="openingTimesCarWash")
    payment_methods: PaymentMethods = Field(..., alias="paymentMethods")
    fuel_types: FuelTypes = Field(..., alias="fuelTypes")


class Example(BaseModel):
    hash_key: int = Field(..., alias="hashKey")
    range_key: str = Field(..., alias="rangeKey")
    location_id: str = Field(..., alias="locationId")
    name: str = Field(..., alias="name")
    street: str = Field(..., alias="street")
    address_number: str = Field(..., alias="addressNumber")
    zip_code: int = Field(..., alias="zipCode")
    city: str = Field(..., alias="city")
    region: str = Field(..., alias="region")
    country: str = Field(..., alias="country")
    additional_info: Union[AdditionalInfoStation] = Field(..., alias="additionalInfo")


class ExampleList(BaseCollectionModel[EniGeoPoint]):
    pass

2. Imagine that there is an ExampleList populated object and needed filters field during apply of dict method:

example_list: ExampleList = ExampleList.parse_obj([{......}])

#This istruction raised exception
example_list.dict(by_alias=True, inlcude={"hash_key", "range_key"})

3. The last istruction raise an error: Message: KeyError('__root__')

My env is:

• pydantic==1.9.1
• pydantic-collections==0.2.0
• python version 3.9.7

If you need more info please contact me.