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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 is_vertex_cover(G, vertex_cover):
 """Determines whether the given set of vertices is a vertex cover of graph G. A vertex cover is a set of vertices such that each edge of the graph is incident with at least one vertex in the set. Parameters G : NetworkX graph The graph on which to check the vertex cover. vertex_cover : Iterable of nodes. Returns ------- is_cover : bool True if the given iterable forms a vertex cover. Examples -------- This example checks two covers for a graph, G, of a single Chimera unit cell. The first uses the set of the four horizontal qubits, which do constitute a cover; the second set removes one node. True False """

    cover = set(vertex_cover)
    return all(u in cover or v in cover for u, v in G.edges)