ValidatedDC - Dataclass with data validation

[EvgeniyBurdin]

For example:

from validated_dc import ValidatedDC
from dataclasses import dataclass

from typing import List, Union


@dataclass
class Foo(ValidatedDC):
    foo: int


@dataclass
class Bar(ValidatedDC):
    bar: Union[Foo, List[Foo]]


foo = {'foo': 1}
instance = Bar(bar=foo)
print(instance.get_errors())  # None
print(instance)               # Bar(bar=Foo(foo=1))

list_foo = [{'foo': 1}, {'foo': 2}]
instance = Bar(bar=list_foo)
print(instance.get_errors())  # None
print(instance)               # Bar(bar=[Foo(foo=1), Foo(foo=2)])