@property
def colwidth(self):
    if (len(self.edges) == 0):
        return 1
    else:
        x2 = max((e.right_node.xy.x for e in self.edges))
        return ((x2 - self.xy.x) + 1)
@property
def colwidth(self):
    if (len(self.edges) == 0):
        return 1
    else:
        x2 = max((e.right_node.xy.x for e in self.edges))
        return ((x2 - self.xy.x) + 1)