Add mult, but it doesn't quite work

ChaCha20_Poly1305_64/sim/do_poly_1305.py

@@ -1,4 +1,5 @@
 from typing import List
+import random
 
 from modulo_theory import friendly_modular_mult, friendly_modulo
 
@@ -111,11 +112,19 @@ def test_on_long_string():
     print(f"{regular_result:x}")
     print(f"{parallel_result:x}")
 
+def test_random():
+    r = mask_r(random.randint(0, 2**128-1))
+    s = random.randint(0, 2**128-1)
+
+    msg = random.randbytes(random.randint(16, 1500))
+
+    parallel_poly1305(msg, r, s, 8)
 
 def main():
     test_regular()
     test_parallel()
     test_on_long_string()
+    test_random()
 
 if __name__ == "__main__":
     main()