PyDiGraph Type Hinting not working, TypeError: 'type' object is not subscriptable

[drauh]

Information

• rustworkx version: 0.15.1
• Python version: 3.9, 3.11 and 3.10 (Colab)
• Rust version: None
• Operating system: Ubuntu 22.04 and Google Colab

What is the current behavior?

import rustworkx as rx

graph: rx.PyDiGraph[str, str] = rx.PyDiGraph()

import rustworkx as rx
----> graph: rx.PyDiGraph[str, str] = rx.PyDiGraph()

TypeError: 'type' object is not subscriptable

What is the expected behavior?

It seems that other users manage to use type hinting as shown in #1242. I can't understand why it doesn't work on both systems I tested, and I can't find anything in the documentation about it.

Steps to reproduce the problem

Go to Google Colab and run:

!pip install rustworkx[all]
import sys
print(sys.version)
!ldd --version
import rustworkx as rx

graph: rx.PyDiGraph[str, str] = rx.PyDiGraph()

[IvanIsCoding]

Try using from __future__ import annotations. This works fine:

from __future__ import annotations

import rustworkx as rx

graph: rx.PyDiGraph[str, str] = rx.PyDiGraph()

Notice that it works out of the box on newer Python versions.

[drauh]

Thank you very much for your answer. I apologize for not trying the from __future__ import annotations earlier. I can confirm that using this approach works on Python versions 3.9 through 3.12. However, without using the __future__ import, the code still doesn't work, even on Python 3.12.4 (I just created a brand new environment for testing this).

That said, this solution does indeed solve the problem for me. Thank you!

[IvanIsCoding]

I guess PEP 563 is not yet mandatory in any version so you are correct. All versions need the __future__ mechanism