class A:
    def __init__(self, txt: str):
        self.u: F = None
        self.t: C = None
        self.z: F = None
        self.q: G = None
        self.v: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.r: F = None
        self.z: F = None
        self.u: G = None
        self.y: A = None
        self.o: G = None
        self.t: H = None
        self.s: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.q: E = None
        self.p: D = None
        self.v: F = None
        self.x: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.q: B = None
        self.t: B = None
        self.s: B = None
        self.z: F = None
        self.o: C = None
        self.y: B = None
        self.v: H = None
        self.r: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: D = None
        self.z: H = None
        self.p: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.x: D = None
        self.s: E = None
        self.y: F = None
        self.v: B = None
        self.txt = txt

n = A("n")
j = B("j")
i = C("i")
a = D("a")
e = E("e")
c = F("c")
k = G("k")
l = H("l")

n.u = c
n.z = c
n.t = i
n.v = i
n.q = k
j.r = c
j.z = c
j.s = c
j.u = k
j.o = k
j.y = n
j.t = l
i.q = e
i.p = a
i.v = c
i.x = l
a.q = j
a.t = j
a.s = j
a.y = j
a.z = c
a.o = i
a.v = l
a.r = e
e.x = l
c.r = l
k.u = a
k.z = l
k.p = l
l.x = a
l.s = e
l.y = c
l.v = j
assert a.z.r.s.x.v.t.v.r.txt == "
class A:
    def __init__(self, txt: str):
        self.u: F = None
        self.t: C = None
        self.z: F = None
        self.q: G = None
        self.v: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.r: F = None
        self.z: F = None
        self.u: G = None
        self.y: A = None
        self.o: G = None
        self.t: H = None
        self.s: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.q: E = None
        self.p: D = None
        self.v: F = None
        self.x: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.q: B = None
        self.t: B = None
        self.s: B = None
        self.z: F = None
        self.o: C = None
        self.y: B = None
        self.v: H = None
        self.r: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: D = None
        self.z: H = None
        self.p: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.x: D = None
        self.s: E = None
        self.y: F = None
        self.v: B = None
        self.txt = txt

n = A("n")
j = B("j")
i = C("i")
a = D("a")
e = E("e")
c = F("c")
k = G("k")
l = H("l")

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