Apply remaining review suggestions:

 * Fix details after applying inline suggestions
 * Keep TwoQubitWeilDecomposition attributes private. Add getter.
 * Initialize new_blocks using size hint
 * Remove basis_set as it's not used if there is a target.
 * Use ref_qubits ([PhysicalQubit; 2]) instead of wire_map (IndexMap<Qubit, Physicalqubit>)
 * Define static GOODBYE_SET as suggested
 * Use ImportOnceCell for XXDecomposer and XXEmbodiments to avoid importing in a loop.
 * Set preferred_direction without making it mutable.
 * Fix check_goodbye
 * Privatize assets
 * Use the add_global_phase method instead of the private function.
 * Add qs_decomposition to imports
 * Simplify flip_bits
 * Use NormalOperation to pass around decomposer gate and params info
 * First attempt at attaching synth circuits directly
 * Second attempt at attaching synth circuits directly
 * Use edge set for coupling map
 * Avoid exposing internals from NullableIndexMap
 * Use unitary_to_gate_sequence_inner instead of optimize_1q_gates_decomposition.
 * Use concat! in long error message.

crates/accelerate/src/target_transpiler/nullable_index_map.rs

@@ -42,7 +42,7 @@ where
     K: Eq + Hash + Clone,
     V: Clone,
 {
-    pub map: BaseMap<K, V>,
+    map: BaseMap<K, V>,
     null_val: Option<V>,
 }
 

crates/accelerate/src/two_qubit_decompose.rs

@@ -404,11 +404,11 @@ impl Specialization {
 #[pyclass(module = "qiskit._accelerate.two_qubit_decompose", subclass)]
 pub struct TwoQubitWeylDecomposition {
     #[pyo3(get)]
-    pub a: f64,
+    a: f64,
     #[pyo3(get)]
-    pub b: f64,
+    b: f64,
     #[pyo3(get)]
-    pub c: f64,
+    c: f64,
     #[pyo3(get)]
     pub global_phase: f64,
     K1l: Array2<Complex64>,
@@ -426,6 +426,15 @@ pub struct TwoQubitWeylDecomposition {
 }
 
 impl TwoQubitWeylDecomposition {
+    pub fn a(&self) -> &f64 {
+        &self.a
+    }
+    pub fn b(&self) -> &f64 {
+        &self.b
+    }
+    pub fn c(&self) -> &f64 {
+        &self.c
+    }
     fn weyl_gate(
         &self,
         simplify: bool,