class A:
    def __init__(self, txt: str):
        self.y: G = None
        self.p: F = None
        self.t: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: A = None
        self.s: A = None
        self.y: H = None
        self.t: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: B = None
        self.r: H = None
        self.v: H = None
        self.u: D = None
        self.t: B = None
        self.o: F = None
        self.s: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.w: H = None
        self.x: G = None
        self.v: B = None
        self.z: G = None
        self.t: E = None
        self.s: B = None
        self.r: A = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.y: H = None
        self.x: B = None
        self.o: C = None
        self.q: D = None
        self.r: E = None
        self.u: C = None
        self.z: E = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.q: A = None
        self.s: A = None
        self.y: H = None
        self.t: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: B = None
        self.r: H = None
        self.v: H = None
        self.u: D = None
        self.t: B = None
        self.o: F = None
        self.s: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.w: H = None
        self.x: G = None
        self.v: B = None
        self.z: G = None
        self.t: E = None
        self.s: B = None
        self.r: A = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.y: H = None
        self.x: B = None
        self.o: C = None
        self.q: D = None
        self.r: E = None
        self.u: C = None
        self.z: E = None
        self.txt = txt

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

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

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