class A:
    def __init__(self, txt: str):
        self.x: C = None
        self.s: E = None
        self.o: C = None
        self.u: D = None
        self.y: A = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.o: B = None
        self.p: A = None
        self.t: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.u: B = None
        self.w: B = None
        self.o: E = None
        self.r: A = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.v: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.o: B = None
        self.p: A = None
        self.t: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.u: B = None
        self.w: B = None
        self.o: E = None
        self.r: A = None
        self.txt = txt

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

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

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