Fix: Use is to avoid obtaining the gil.

- Remove `Display` trait.

crates/circuit/src/operations.rs

@@ -177,38 +177,13 @@ impl PartialEq for Param {
     fn eq(&self, other: &Self) -> bool {
         match (self, other) {
             (Param::Float(s), Param::Float(other)) => s == other,
-            (Param::ParameterExpression(one), Param::ParameterExpression(other)) => {
-                compare(one, other)
-            }
-            (Param::Obj(one), Param::Obj(other)) => compare(one, other),
+            (Param::ParameterExpression(one), Param::ParameterExpression(other)) => one.is(other),
+            (Param::Obj(one), Param::Obj(other)) => one.is(other),
             _ => false,
         }
     }
 }
 
-impl std::fmt::Display for Param {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        let display_name: String = Python::with_gil(|py| -> PyResult<String> {
-            match self {
-                Param::ParameterExpression(obj) => obj.call_method0(py, "__repr__")?.extract(py),
-                Param::Float(float_param) => Ok(format!("Parameter({})", float_param)),
-                Param::Obj(obj) => obj.call_method0(py, "__repr__")?.extract(py),
-            }
-        })
-        .unwrap_or("None".to_owned());
-        write!(f, "{}", display_name)
-    }
-}
-
-/// Perform comparison between two Python objects
-pub fn compare(one: &PyObject, other: &PyObject) -> bool {
-    Python::with_gil(|py| -> PyResult<bool> {
-        let other_bound = other.bind(py);
-        Ok(other_bound.eq(one)? || other_bound.is(one))
-    })
-    .unwrap_or_default()
-}
-
 #[derive(Clone, Debug, Copy, Eq, PartialEq, Hash)]
 #[pyclass(module = "qiskit._accelerate.circuit")]
 pub enum StandardGate {