refactor: replace multiple == checks with in

To check if a variable is equal to one of many values, combine the values into a tuple and check if the variable is contained `in` it instead of checking for equality against each of the values.
This is faster, less verbose, and more readable.

python/utils.py

@@ -12,7 +12,7 @@ def is_even(x):
         return x % 2 == 0
 
     def is_prime(x):
-        if x == 0 or x == 1:
+        if x in (0, 1):
             return False
 
         for i in range(2, x):