Expose job cost estimation values (#976)

* Expose job cost estimation values

* address comments

* fix black

* Update qiskit_ibm_runtime/runtime_job.py

Co-authored-by: Jessie Yu <jessieyu@us.ibm.com>

* fix black, update reno

---------

Co-authored-by: Jessie Yu <jessieyu@us.ibm.com>

qiskit_ibm_runtime/runtime_job.py

@@ -138,6 +138,7 @@ def __init__(
         self._service = service
         self._session_id = session_id
         self._tags = tags
+        self._usage_estimation: Dict[str, Any] = {}
 
         decoder = result_decoder or DEFAULT_DECODERS.get(program_id, None) or ResultDecoder
         if isinstance(decoder, Sequence):
@@ -655,3 +656,20 @@ def tags(self) -> List:
             Tags assigned to the job that can be used for filtering.
         """
         return self._tags
+
+    @property
+    def usage_estimation(self) -> Dict[str, Any]:
+        """Return the usage estimation infromation for this job.
+
+        Returns:
+            ``quantum_seconds`` which is the estimated quantum time
+            of the job in seconds. Quantum time represents the time that
+            the QPU complex is occupied exclusively by the job.
+        """
+        if not self._usage_estimation:
+            response = self._api_client.job_get(job_id=self.job_id())
+            self._usage_estimation = {
+                "quantum_seconds": response.pop("estimated_running_time_seconds", None),
+            }
+
+        return self._usage_estimation

releasenotes/notes/job-cost-estimation-d0ba83dbc95c3f67.yaml

@@ -0,0 +1,6 @@
+---
+features:
+  - |
+    Added a new property, :meth:`~qiskit_ibm_runtime.RuntimeJob.usage_estimation`
+    that returns the estimated running time, ``quantum_seconds``. Quantum time 
+    represents the time that the QPU complex is occupied exclusively by the job.

test/integration/test_job.py

@@ -286,6 +286,14 @@ def test_job_metrics(self, service):
         self.assertIn("timestamps", metrics)
         self.assertIn("qiskit_version", metrics)
 
+    @run_integration_test
+    def test_usage_estimation(self, service):
+        """Test job usage estimation"""
+        job = self._run_program(service)
+        job.wait_for_final_state()
+        self.assertTrue(job.usage_estimation)
+        self.assertIn("quantum_seconds", job.usage_estimation)
+
     @run_integration_test
     def test_updating_job_tags(self, service):
         """Test job metrics."""