All details I have about rust-cpython are that it fails tests with:

    AttributeError: module 'unicodedata' has no attribute 'ucnhash_CAPI'

See the test failures in https://koschei.fedoraproject.org/package/rust-cpython e.g.:

---- src/objects/capsule.rs - objects::capsule::PyCapsule (line 34) stdout ----
Test executable failed (exit code 101).
stderr:
thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: PyErr { ptype: <class 'AttributeError'>, pvalue: Some(AttributeError("module 'unicodedata' has no attribute 'ucnhash_CAPI'")), ptraceback: None }', src/objects/capsule.rs:77:2
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
---- src/objects/capsule.rs - py_capsule (line 232) stdout ----
Test executable failed (exit code 101).
stderr:
thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: PyErr { ptype: <class 'AttributeError'>, pvalue: Some(AttributeError("module 'unicodedata' has no attribute 'ucnhash_CAPI'")), ptraceback: None }', src/objects/capsule.rs:73:47
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
failures:
    src/objects/capsule.rs - objects::capsule::PyCapsule (line 34)
    src/objects/capsule.rs - py_capsule (line 232)

(Note that there are also other failures regarding an implicit float->int conversion, but they seem to be caused by a change that followed the deprecation period.)