Updated at_cache (markdown)

at_cache.md

@@ -4,4 +4,15 @@ The @cache decorator can be imported with.
 ```python
 from functools import cache
 
+@cache
+def mod25(num):
+  return num%25
+
+def some_loop_function(iterations=1000):
+  for i in iterations:
+    mod25(i)
+
+if __name__ == "__main__":
+  some_loop_function()
+  some_loop_function(1200)
 ```