class A:
    def __init__(self, txt: str):
        self.s: D = None
        self.u: G = None
        self.p: C = None
        self.o: B = None
        self.z: D = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.o: G = None
        self.p: A = None
        self.u: A = None
        self.w: A = None
        self.y: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: B = None
        self.v: G = None
        self.t: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: F = None
        self.q: C = None
        self.o: A = None
        self.t: B = None
        self.r: F = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.p: B = None
        self.z: C = None
        self.t: D = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.o: G = None
        self.p: A = None
        self.u: A = None
        self.w: A = None
        self.y: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: B = None
        self.v: G = None
        self.t: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: F = None
        self.q: C = None
        self.o: A = None
        self.t: B = None
        self.r: F = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.p: B = None
        self.z: C = None
        self.t: D = None
        self.txt = txt

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

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