Is there a closed form formula exists to count the number of non-perfect matchings in a bipartite graph given vertices and egdes count?

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Given a bipartite graph with v vertices each side, and initially, all vertices are disconnected i.e., 0 edges were in the graph initially, how to count the number of ways of introducing v+2 or v+3 edges such that no perfect matching exists?

Any help is much appreciated. Counting each such combination seems very hard and I think that would not be the right approach as the total number of ways could be huge. Any help, topics, links, suggestions would be appreciated.