Hello. Is there no builtin mechanism for serializing

TypeVar

instances? If not are there any recommendations to handle them?

@mammoth-artist-36380 I think this PR introduced support for using

typing.Annotated

instead

It's hard for me to tell, is this specific to

FlyteFile

?

What do you mean type at instances can you share an example

We actually found the issue here. It happens when a task has an input / output that includes a generic

TypeVar

. These get added to the task

Interface

which gets passed down the stack and handed to

to_python_value

expected_python_type

on a custom

TypeTransformer

. At serialization time, the actual type is known in place of the

TypeVar

but during deserialization, our deserializer was getting confused because it was trying to deserialize to the

TypeVar

instead of the concrete type since that's what comes in to

to_python_value

. The workaround we found is to explicitly serialize the concrete type information in place of the

TypeVar

alongside the serialized object and then ignore the type information passed into

to_python_value

and instead use the serialized type information.