class Solution:
    def permute(self, nums: List[int]) -> List[List[int]]:

        # Base Case
        if not len(nums):
            return [[]]

        result = []
        for i in range(len(nums)):

            # let's assume it returns a list of lists
            # of all possible permutations except the
            # element in question/iterating over
            permutations = self.permute(nums[:i] + nums[i+1:])

            # add the element in question as a leading element
            # to the generated permutations and add each list
            # to the final result
            for j in range(len(permutations)):
                permutations[j] = [nums[i]] + permutations[j]

            # Gather final result and add list of lists to the
            # to the accumulator result variable
            result += permutations

        return result