twoSum Algorithm : How to improve this?

Question

I felt like doing an algorithm and found this problem on leetcode

Given an array of integers, find two numbers such that they add up to a specific target num

Answer 1

One line solution in python :

class Solution(object):
    """
        :type nums: List[int]
        :type target: int
        :rtype: List[int]
    """
    def twoSum(self, nums, target):            
        x = [[i, nums.index(target-j)] for i,j in enumerate(nums) if nums.count(target-j) > 0 and nums.index(target-j)!=i]

        return x.pop()