Update snippet descriptions

snippets/rgb_to_hex.md

@@ -5,12 +5,12 @@ tags: string,math,intermediate
 
 Converts the values of RGB components to a hexadecimal color code.
 
-- Create a placeholder for a zero-padded hexadecimal value using `"{:02X}"`, copy it three times.
+- Create a placeholder for a zero-padded hexadecimal value using `'{:02X}'` and copy it three times.
 - Use `str.format()` on the resulting string to replace the placeholders with the given values.
 
 ```py
 def rgb_to_hex(r, g, b):
-  return ("{:02X}" * 3).format(r, g, b)
+  return ('{:02X}' * 3).format(r, g, b)
 ```
 
 ```py