Get attribute value function

Change-Id: Iab7fc4d00a9341cf3b5cb794696b900e44b2f4a1
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/lib/bmc_redfish.py b/lib/bmc_redfish.py
index 178a207..0619ca5 100644
--- a/lib/bmc_redfish.py
+++ b/lib/bmc_redfish.py
@@ -132,6 +132,22 @@
         """
         self._robj_.logout()
 
+    def get_attribute(self, resource_path, attribute):
+        r"""
+        Perform a GET request and return attribute value.
+
+        Description of argument(s):
+        resource_path    URI resource absolute path (e.g. "/redfish/v1/Systems/1").
+        attribute        Property name (e.g. "PowerState").
+        """
+
+        resp = self._robj_.get(resource_path)
+
+        if attribute in resp.dict:
+            return resp.dict[attribute]
+
+        return None
+
     def list_request(self, resource_path):
         r"""
         Perform a GET list request and return available resource paths.