class A:
    def __init__(self, txt: str):
        self.u: C = None
        self.p: E = None
        self.z: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.w: A = None
        self.r: D = None
        self.t: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.q: D = None
        self.y: A = None
        self.w: D = None
        self.u: B = None
        self.t: C = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: A = None
        self.y: B = None
        self.u: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: E = None
        self.x: B = None
        self.s: E = None
        self.o: E = None
        self.txt = txt

l = A("l")
e = B("e")
n = C("n")
k = D("k")
h = E("h")
f = E("f")
i = C("i")

l.u = i
l.p = h
l.z = k
e.w = l
e.r = k
e.t = n
n.q = k
n.w = k
n.y = l
n.u = e
n.t = i
k.p = l
k.y = e
k.u = f
h.t = f
h.s = f
h.o = f
h.x = e
f.t = h
f.s = h
f.o = h
f.x = e
i.q = k
i.w = k
i.y = l
i.u = e
i.t = n
assert l.z.p.z.y.txt == "
class A:
    def __init__(self, txt: str):
        self.u: C = None
        self.p: E = None
        self.z: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.w: A = None
        self.r: D = None
        self.t: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.q: D = None
        self.y: A = None
        self.w: D = None
        self.u: B = None
        self.t: C = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: A = None
        self.y: B = None
        self.u: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: E = None
        self.x: B = None
        self.s: E = None
        self.o: E = None
        self.txt = txt

l = A("l")
e = B("e")
n = C("n")
k = D("k")
h = E("h")
f = E("f")
i = C("i")

l.u = i
l.p = h
l.z = k
e.w = l
e.r = k
e.t = n
n.q = k
n.w = k
n.y = l
n.u = e
n.t = i
k.p = l
k.y = e
k.u = f
h.t = f
h.s = f
h.o = f
h.x = e
f.t = h
f.s = h
f.o = h
f.x = e
i.q = k
i.w = k
i.y = l
i.u = e
i.t = n
assert l.z.p.z.y.txt == "e"