class A:
    def __init__(self, txt: str):
        self.t: H = None
        self.u: F = None
        self.q: B = None
        self.o: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: E = None
        self.p: C = None
        self.v: F = None
        self.z: H = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.x: C = None
        self.q: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: I = None
        self.v: F = None
        self.t: F = None
        self.s: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: G = None
        self.v: G = None
        self.s: H = None
        self.p: E = None
        self.w: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.t: B = None
        self.o: C = None
        self.v: F = None
        self.z: B = None
        self.w: G = None
        self.x: A = None
        self.p: C = None
        self.u: C = None
        self.r: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: C = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: H = None
        self.x: F = None
        self.o: C = None
        self.v: B = None
        self.u: E = None
        self.z: B = None
        self.w: C = None
        self.q: H = None
        self.t: C = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.u: E = None
        self.p: C = None
        self.v: F = None
        self.z: H = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.x: C = None
        self.q: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: I = None
        self.v: F = None
        self.t: F = None
        self.s: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: G = None
        self.v: G = None
        self.s: H = None
        self.p: E = None
        self.w: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.t: B = None
        self.o: C = None
        self.v: F = None
        self.z: B = None
        self.w: G = None
        self.x: A = None
        self.p: C = None
        self.u: C = None
        self.r: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: C = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: H = None
        self.x: F = None
        self.o: C = None
        self.v: B = None
        self.u: E = None
        self.z: B = None
        self.w: C = None
        self.q: H = None
        self.t: C = None
        self.txt = txt

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

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