Fix examples

evaluation_examples/examples/os/c56de254-a3ec-414e-81a6-83d2ce8c41fa.json

@@ -1,17 +1,34 @@
 {
     "id": "c56de254-a3ec-414e-81a6-83d2ce8c41fa",
     "snapshot": "os",
-    "instruction": "Could you please help me to extract text from a non-indexed PDF document on the current system?",
+    "instruction": "I want to install the lxml package on my ubuntu system. Can you help me?",
     "source": "https://superuser.com/questions/28426/how-to-extract-text-with-ocr-from-a-pdf-on-linux",
+    "config": [
+      {
+        "type": "execute",
+        "parameters": {
+          "command": "sudo apt-get update && sudo apt-get install -y python3",
+          "shell": true
+        }
+      }
+    ],
     "trajectory": "trajectories/",
     "related_apps": [
       "os"
     ],
     "evaluator": {
-      "func": "",
+      "func": "exact_match",
       "result": {
+        "type": "vm_command_line",
+        "command": "python3 -c \"import lxml\" >/dev/null 2>&1 && echo \"lxml is installed\" || echo \"lxml is not installed\"",
+        "shell": true
       },
       "expected": {
+        "type": "rule",
+        "rules":{
+          "expected": "lxml is installed"
+        }
       }
     }
-  }
+  }
+