def __contains__(self,n):
        """Return True if n is a node, False otherwise. Use the expression
        'n in G'.

        Examples
        --------
        >>> G = nx.Graph()   # or DiGraph, MultiGraph, MultiDiGraph, etc
        >>> G.add_path([0,1,2,3])
        >>> 1 in G
        True
        """
        try:
            return n in self.node
        except __HOLE__:
            return False
dataset/ETHPy150Open gkno/gkno_launcher/src/networkx/classes/graph.py/Graph.__contains__