class Node(object):
    def __init__(self, value=None):
        self.high = None
        self.low = None
        self.value = value

    def __call__(self):
        return self.value

root = Node(2)
root.high = Node(5)
root.low = Node(1)
root.high.low = Node(3)

def find_value_or_lower(value, node, closest=None):
    print node.__dict__
    if node() == value:
    return node()

    if node() < value:
        if not closest:
            closest=node()
        elif (value - closest) > (value - node()):
            closest=node()

        if node.high:
            return find_value_or_lower(value, node.high, closest)
    else:
            return closest

    if node() > value:
    if node.low:
            return find_value_or_lower(value, node.low, closest)
    else:
            return closest

print find_value_or_lower(4, root)

root = Node(8)
root.high = Node(10)
root.low = Node(3)
root.high.high = Node(14)
root.high.high.low = Node(13)
root.low.low = Node(1)
root.low.high = Node(6)
root.low.high.low = Node(4)
root.low.high.high = Node(7)

print find_value_or_lower(7, root)