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diff --git a/challenge-245/ianrifkin/python/ch-2.py b/challenge-245/ianrifkin/python/ch-2.py
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+#!/usr/local/bin/python3
+import sys, argparse
+import math
+from itertools import permutations
+
+# Task 2: Largest of Three
+
+# You are given an array of integers >= 0.
+
+# Write a script to return the largest number formed by concatenating some of the given integers in any order which is also multiple of 3. Return -1 if none found.
+
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-245/#TASK2 for more information on this challenge
+
+def main(argv):
+    argParser = argparse.ArgumentParser()
+    argParser.add_argument("-n", "--nums", nargs='+', type=int, help="space seperated list of positive integers e.g. -n 10 30 4 5")
+    args = argParser.parse_args()
+
+    if args.nums:
+        nums = args.nums
+        print( largest(nums) )
+    else:
+        # Example 1
+        nums = [8, 1, 9]
+        print( largest(nums) )        
+        #Output: 981
+
+        # Example 2
+        nums = [8, 6, 7, 1, 0]
+        print( largest(nums) )        
+        #Output: 8760
+        
+        # Example 3
+        nums = [1]
+        print( largest(nums) )        
+        #Output: -1
+        
+        
+def largest(nums):
+    numbers_to_try = []
+    for i in range(len(nums)):
+        num_of_digits = i+1
+        perms = list(permutations(nums, num_of_digits))
+        
+        for group_of_digits in perms:
+            combined_digits = int("".join(map(str, group_of_digits)))            
+            numbers_to_try.append(combined_digits)
+
+    numbers_to_try.sort(reverse=True)
+    
+    for num2try in numbers_to_try:
+        if num2try % 3 == 0:
+            return num2try
+    return -1
+            
+
+    # # Use array of potential numbers in numerical descending sort order
+    # # to determine if any are divisible by 3
+    # foreach my $num_2_try (sort { $b <=> $a } @numbers_to_try) {
+    #     # return the first (biggest) number found
+    #     return $num_2_try unless $num_2_try % 3;
+    # }
+    # return -1 #default return value of -1 if no number found
+
+    
+                    
+        
+if __name__ == "__main__":
+   main(sys.argv[1:])