Implement most_frequent_value function

solution23.py

@@ -1,2 +1,17 @@
 def most_frequent_value(d: dict) -> tuple:
-    pass
+    frequency = {}
+    for value in d.values():
+        if value in frequency:
+            frequency[value] += 1
+        else:
+            frequency[value] = 1
+    max_value = None
+    max_count = 0
+    for value, count in frequency.items():
+        if count > max_count:
+            max_count = count
+            max_value = value
+    return(max_value, max_count)
+
+if __name__ == "__main__":
+    print(most_frequent_value({"a": 1, "b": 2, "c": 1, "d": 3}))