I'm trying to find the first 3 minimum spanning trees of a single complete and all weights are non-negative graph.

That is finding the minimum spanning tree (which I already can do), THEN find the SECOND minimum spanning tree that is greater than (or possibly) equal to the first minimum spanning tree, then same thing for the third minimum spanning tree.

This problem is NOT about finding THE minimum spanning tree, it IS about finding the next two minimum spanning trees.

Pseudo code or python code please. Also I've been trying to modify Boruvka's algorithm to do this, if possibly please use that as a starting point.

weight: 1st MST

In class, we have seen multiple algorithms for computing minimum spanning trees. In this assignment, we design algorithms for computing the second and third minimum spanning trees For example, the following figure shows a graph, and its first, second, and third minimum spanning 12 12 12 12 6 10