Update syntax highlighting, update allUnique

snippets/is_upper_case.md

@@ -6,12 +6,12 @@ Checks if a string is upper case.
 
 Convert the given string to upper case, using `str.upper()` method and compare it to the original.
 
-```python
+```py
 def is_upper_case(string):
     return string == string.upper()
 ```
 
-```python
+```py
 is_upper_case('ABC') # True
 is_upper_case('a3@$') # False
 is_upper_case('aB4') # False