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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def vertex_adjacency_graph(mesh):
 """ Returns a networkx graph representing the vertices and their connections in the mesh. Parameters mesh : Trimesh object Returns --------- graph : networkx.Graph Graph representing vertices and edges between them where vertices are nodes and edges are edges Examples This is useful for getting nearby vertices for a given vertex, potentially for some simple smoothing techniques. > [1,3,4] """

    g = nx.Graph()
    g.add_edges_from(mesh.edges_unique)
    return g