Returns True if and only if
Gis a tournament.
A tournament is a directed graph, with neither self-loops nor multi-edges, in which there is exactly one directed edge joining each pair of distinct nodes.
Parameters: G (NetworkX graph) – A directed graph representing a tournament. Returns: Whether the given graph is a tournament graph. Return type: bool
Some definitions require a self-loop on each node, but that is not the convention used here.