add instances method (#1040)

qiskit_ibm_runtime/qiskit_runtime_service.py

@@ -1498,6 +1498,16 @@ def least_busy(
             raise QiskitBackendNotFoundError("No backend matches the criteria.")
         return min(candidates, key=lambda b: b.status().pending_jobs)
 
+    def instances(self) -> List[str]:
+        """Return the IBM Quantum instances list currently in use for the session.
+
+        Returns:
+            A list with instances currently in the session.
+        """
+        if self._channel == "ibm_quantum":
+            return list(self._hgps.keys())
+        return []
+
     @property
     def auth(self) -> str:
         """Return the authentication type used.

releasenotes/notes/instances-method-02fda1de98638e59.yaml

@@ -0,0 +1,6 @@
+---
+features:
+  - |
+    Added a new method, :meth:`qiskit_ibm_runtime.QiskitRuntimeService.instances` that returns
+    all instances(hub/group/project) the user is in. This is only for the ``ibm_quantum`` channel
+    since the ``ibm_cloud`` channel does not have multiple instances.