Generic GraphMl Printer
Graph information required by Graphml
List of the type of the vertex proprierties.
The format is (id,type,default).
List of the type of the edge proprierties.
Associates to each vertex a key/value list where
the key is the id of a vertex attribute and the value is the value
associated to this vertex
Associates to each edge a key/value list
Graphml Printer given a graph and required info
print fmt graph print the GraphMl representation of the given graph
on the given formatter
print fmt graph