Add dataset card

README.md

@@ -2234,7 +2234,21 @@ desc_stats = task.metadata.descriptive_stats
 ```
 
 ```json
-{}
+{
+    "test": {
+        "num_samples": 518144,
+        "number_of_characters": 162367876,
+        "unique_pairs": 518101,
+        "min_sentence1_length": 9,
+        "average_sentence1_length": 156.6821925951087,
+        "max_sentence1_length": 692,
+        "unique_sentence1": 23550,
+        "min_sentence2_length": 9,
+        "average_sentence2_length": 156.6821925951087,
+        "max_sentence2_length": 692,
+        "unique_sentence2": 23550
+    }
+}
 ```
 
 </details>