class A:
    def __init__(self, txt: str):
        self.u: F = None
        self.x: F = None
        self.v: H = None
        self.z: H = None
        self.s: F = None
        self.w: D = None
        self.t: H = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.r: A = None
        self.y: A = None
        self.w: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: B = None
        self.p: D = None
        self.o: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: G = None
        self.v: B = None
        self.y: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: F = None
        self.w: F = None
        self.o: H = None
        self.x: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: E = None
        self.t: D = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.r: A = None
        self.y: A = None
        self.w: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: B = None
        self.p: D = None
        self.o: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: G = None
        self.v: B = None
        self.y: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: F = None
        self.w: F = None
        self.o: H = None
        self.x: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: E = None
        self.t: D = None
        self.txt = txt

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

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