# Question Please complete: * OS: Ubuntu 18.04 * Python version `import sys; print(sys.version)`: 3.6.8 [GCC 7.4.0] * Pydantic version `import pydantic; print(pydantic.VERSION)`: 1.2a1 Hello, I'm trying to create an instance of class Bar. ```py import pydantic from typing import List class Foo(pydantic.BaseModel): foo: List[List[int]] @pydantic.validator('foo') def check_something(cls, value): return value class Bar(Foo): pass foo_ = [[0, 1]] Foo(foo=foo_) Bar(foo=foo_) ``` Output: ``` pydantic.error_wrappers.ValidationError: 1 validation error for Bar foo -> 0 value is not a valid integer (type=type_error.integer) ``` There will be no error, If you remove validator.