We should not be adding all edges. We should set it up so that there is only one edge in each direction for each node. In each case, if the existing edge is more costly, we should replace that edge, rather than append a new/different one to the same directional node pair.
On these lines: https://github.com/kuanb/peartree/blob/e37dbcb7031049e36e9213bd92780c3b4e1f05e8/peartree/toolkit.py#L201-L206
We should not be adding all edges. We should set it up so that there is only one edge in each direction for each node. In each case, if the existing edge is more costly, we should replace that edge, rather than append a new/different one to the same directional node pair.