I was wondering if the push_relabel_max_flow algorithm can be used in multigraphs.
I mean, can I have two vertices joined by two edges: one in a direction an the other in the opposite direction with equal capacities ( 1000 for example ).

It is clear in the documentation that the reverse edge must exist for each edge in the graph, so there must be 4 edges in the case I am describing.
but the question is:
does the algorithm works properly for this case ?