Find all the subsets of the array

'''
Here we are taking one subarray and then push all the current elments one by one
'''
class Solution:
    def subsets(self, arr):
        ans=[[]]
        for i in arr:
            new_subset=[]
            for subset in ans:
                new_subset.append(subset+[i])
            ans=ans+new_subset #'+' basically extend the array
        return ans