formating fixed

README.md

@@ -1752,13 +1752,13 @@ set([food for bro in x for food in bro['food']])
 <summary>How to reverse a string?</summary><br><b>
 
 Shortest way is: <code>my_string[::-1]</code> but it doesn't mean it's the most efficient one. <br>
-Cassic way is: <code>
+Cassic way is: ```
 def reverse_string(string):
     temp = ""
     for char in string:
         temp =  char + temp
     return temp
-</code></b></details>
+```</b></details>
 
 <details>
 <summary>Write a function to determine if a given string is a palindrome</summary><br><b>