def graph_setitem(self, node, target):
    "This method exists only to support g[n]+=o.  Do not use as g[n]=foo."
    node = self.pack_source(node)
    try:
        if node == target.fromNode:
            return
    except __HOLE__:
        pass
    raise ValueError('Incorrect usage. Add edges using g[n]+=o or \
g[n][o]=edge.')
dataset/ETHPy150Open cjlee112/pygr/pygr/mapping.py/graph_setitem