Add stubs for other queues

src/lib.rs

@@ -2,11 +2,13 @@ pub mod backing;
 pub mod queue;
 
 use pyo3::prelude::*;
-use queue::paired::PairedQueue;
+use queue::{IndexedQueue, PairedQueue, PureQueue};
 
 /// Bindings for the Rust queue implementations
 #[pymodule]
 fn pyority_queue(m: &Bound<'_, PyModule>) -> PyResult<()> {
+    m.add_class::<PureQueue>()?;
     m.add_class::<PairedQueue>()?;
+    m.add_class::<IndexedQueue>()?;
     Ok(())
 }