class A:
    def __init__(self, txt: str):
        self.v: E = None
        self.q: E = None
        self.u: E = None
        self.o: A = None
        self.z: E = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.r: D = None
        self.z: C = None
        self.y: D = None
        self.q: E = None
        self.txt = txt

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

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

n = A("n")
a = B("a")
k = C("k")
b = D("b")
h = E("h")
i = A("i")
e = A("e")
g = E("g")
c = D("c")
l = C("l")

n.v = h
n.z = h
n.q = g
n.u = g
n.o = i
a.x = h
a.t = i
k.r = c
k.z = l
k.y = b
k.q = h
b.z = g
h.y = c
h.q = c
h.u = k
h.p = b
i.v = g
i.q = h
i.u = h
i.z = h
i.o = n
e.v = h
e.q = h
e.u = h
e.o = n
e.z = g
g.y = c
g.p = c
g.u = k
g.q = b
c.z = h
l.r = c
l.z = k
l.y = b
l.q = g
assert a.x.p.z.q.z.p.z.u.txt == "
class A:
    def __init__(self, txt: str):
        self.v: E = None
        self.q: E = None
        self.u: E = None
        self.o: A = None
        self.z: E = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.r: D = None
        self.z: C = None
        self.y: D = None
        self.q: E = None
        self.txt = txt

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

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

n = A("n")
a = B("a")
k = C("k")
b = D("b")
h = E("h")
i = A("i")
e = A("e")
g = E("g")
c = D("c")
l = C("l")

n.v = h
n.z = h
n.q = g
n.u = g
n.o = i
a.x = h
a.t = i
k.r = c
k.z = l
k.y = b
k.q = h
b.z = g
h.y = c
h.q = c
h.u = k
h.p = b
i.v = g
i.q = h
i.u = h
i.z = h
i.o = n
e.v = h
e.q = h
e.u = h
e.o = n
e.z = g
g.y = c
g.p = c
g.u = k
g.q = b
c.z = h
l.r = c
l.z = k
l.y = b
l.q = g
assert a.x.p.z.q.z.p.z.u.txt == "k"