class A:
    def __init__(self, txt: str):
        self.s: C = None
        self.w: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: C = None
        self.x: D = None
        self.v: D = None
        self.p: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: E = None
        self.s: E = None
        self.t: A = None
        self.q: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.o: B = None
        self.s: A = None
        self.txt = txt

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

i = A("i")
d = B("d")
f = C("f")
a = D("a")
k = E("k")
n = A("n")
j = C("j")
b = E("b")

i.s = j
i.w = f
d.y = j
d.x = a
d.v = a
d.p = a
f.u = k
f.s = k
f.t = i
f.q = d
a.o = d
a.s = i
k.s = b
k.y = b
k.t = n
k.o = d
n.s = f
n.w = f
j.u = k
j.s = k
j.t = n
j.q = d
b.s = k
b.y = k
b.t = n
b.o = d
assert d.x.s.w.q.y.s.t.txt == "
class A:
    def __init__(self, txt: str):
        self.s: C = None
        self.w: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: C = None
        self.x: D = None
        self.v: D = None
        self.p: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: E = None
        self.s: E = None
        self.t: A = None
        self.q: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.o: B = None
        self.s: A = None
        self.txt = txt

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

i = A("i")
d = B("d")
f = C("f")
a = D("a")
k = E("k")
n = A("n")
j = C("j")
b = E("b")

i.s = j
i.w = f
d.y = j
d.x = a
d.v = a
d.p = a
f.u = k
f.s = k
f.t = i
f.q = d
a.o = d
a.s = i
k.s = b
k.y = b
k.t = n
k.o = d
n.s = f
n.w = f
j.u = k
j.s = k
j.t = n
j.q = d
b.s = k
b.y = k
b.t = n
b.o = d
assert d.x.s.w.q.y.s.t.txt == "n"