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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 intersection_nodes(waynodes):
 """ Returns a set of all the nodes that appear in 2 or more ways. Parameters waynodes : pandas.DataFrame Mapping of way IDs to node IDs as returned by `ways_in_bbox`. Returns ------- intersections : set Node IDs that appear in 2 or more ways. """

    counts = waynodes.node_id.value_counts()
    return set(counts[counts > 1].index.values)