leetcode 26: remove duplicates : python solution

LeetCode problem 26, **"Remove Duplicates from Sorted Array,"** requires modifying a sorted array in-place to remove duplicates such that each unique element appears only once. The goal is to return the number of unique elements (`k`) while ensuring the first `k` elements of the array contain these unique values. This is achieved using a two-pointer approach: one pointer (`i`) iterates through the array, and the other (`j`) tracks the position to overwrite with unique elements. This problem tests understanding of in-place array manipulation and efficient use of pointers. The solution has O(n) time complexity and O(1) space complexity.