title: How to add properties to edges when using add_edge_list in graph_tool?
body: <p>I am trying to use <strong>add_edge_list</strong> instead of inserting edges one by one using <strong>add_edge</strong> in order to make the graph creation faster.</p>
  
  <p>But I can't find how I can create these edges at once and associate a weight property to them without looping over the edges once created.</p>