Add import statement for random module

Author: canbula

Week02/weighted_semi_kazar.py

@@ -1,8 +1,9 @@
 import random
+
 def weighted_srs(data, n, weights, with_replacement = False):
     if with_replacement != True or weights is None:
         sample = random.sample(data, n)
     else:
         sample = random.choices(data, weights=weights, k=n)
 
-    return sample
+    return sample