class Solution:
    def groupAnagrams(self, strs):
        ana = dict()
        for s in strs:
            key = ''.join(sorted(s))
            if key in ana:
                ana[key].append(s)
            else:
                ana[key] = [s]
        
        return ana.values()

s = Solution()
print("Expected: [['ate', 'eat', 'tea'], ['nat', 'tan'], ['bat']]")
print("Got:", s.groupAnagrams(["eat", "tea", "tan", "ate", "nat", "bat"]))