add doc and test

docs/en_US/sdk_reference.rst

@@ -8,6 +8,8 @@ Trial
 ..  autofunction:: nni.get_current_parameter
 ..  autofunction:: nni.report_intermediate_result
 ..  autofunction:: nni.report_final_result
+..  autofunction:: nni.get_experiment_id
+..  autofunction:: nni.get_trial_id
 ..  autofunction:: nni.get_sequence_id
 
 

src/sdk/pynni/nni/platform/test.py

@@ -32,10 +32,13 @@ _last_metric = None
 def get_next_parameter():
     return _params
 
-def get_sequence_id():
-    return 0
+def get_experiment_id():
+    return 'fakeidex'
 
 def get_trial_id():
+    return 'fakeidtr'
+
+def get_sequence_id():
     return 0
 
 def send_metric(string):

src/sdk/pynni/tests/test_trial.py

@@ -38,6 +38,12 @@ class TrialTestCase(TestCase):
         nni.get_next_parameter()
         self.assertEqual(nni.get_current_parameter('x'), 123)
 
+    def test_get_experiment_id(self):
+        self.assertEqual(nni.get_experiment_id(), 'fakeidex')
+
+    def test_get_trial_id(self):
+        self.assertEqual(nni.get_trial_id(), 'fakeidtr')
+    
     def test_get_sequence_id(self):
         self.assertEqual(nni.get_sequence_id(), 0)