code is not working

transform.py

@@ -6,17 +6,26 @@
 
 def maximum(data):
     "Returns the largest number in data"
-    raise NotImplementedError
+    highest = None
+    for number in data:
+        if highest is None:
+            highest = number
+        if number > highest:
+           highest = number 
+    return highest       
+    
 
-def minimum(5,10,15):
+def minimum(data):
     lowest = None
     for number in data:
         if lowest is None:
             lowest = number
         if number < lowest:
-           lowest = number 
-    return lowest       
+            lowest = number
+    return lowest      
     "Returns the smallest number in data"
+data = [0, 1, 2, 3]
+print(minimum(data))
    
 
 def bounds(data):