Convex Hull of a set of points, in 2D plane, is a convex polygon with minimum area such that each point lies either on the boundary of polygon or inside it. Now given a set of points the task is to find the convex hull of points.

Example 1:
Input: points_list = {{1,2},{3,1},{5,6}}
Output: {{1,2},{3,1},{5,6}}
Example 2:
Input : points_list = {{5,1},{4,4},{1,2}}
Output: {{1,2},{4,4},{5,1}}

Your Task:
You don't need to read or print anything. Your task is to complete the function FindConvexHull() which takes points_list as input parameter and returns Convex Hull of given points in a list. If not possible returns a list containing -1.

Expected Time Complexity: O(nlog(n))
Expected Space Complexity: O(n) where n = total no. of points

Constraints:
1 <= n <= 10^{4}
-10^{5} <= x, y <= 10^{5}

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