Node.py

class Node():
    def __init__(self, data):
        self.data = data
        self.children = []
    
    def add(self, node):
        self.children.append(node)
        return self
    
    def __str__(self):
        return str(self.data) + "#[" + ",".join([str(c) for c in self.children]) + "]"
    
    def __repr__(self):
        return str(self)
    
    def leaves(self):
        if len(self.children) == 0:
            yield self
        else:
            for c in self.children:
                yield from c.leaves()
                
    def routes_to_leaves(self, acc=[]):
        if len(self.children) == 0:
            yield (acc + [self.data])[1:]
        else:
            for c in self.children:
                yield from c.routes_to_leaves(acc + [self.data])