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

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

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

class D:
    def __init__(self, txt: str):
        self.q: C = None
        self.o: A = None
        self.y: C = None
        self.u: I = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.z: H = None
        self.o: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: G = None
        self.t: E = None
        self.w: F = None
        self.z: E = None
        self.u: C = None
        self.o: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.o: B = None
        self.w: E = None
        self.s: F = None
        self.x: H = None
        self.y: B = None
        self.u: C = None
        self.p: H = None
        self.r: D = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.q: C = None
        self.o: A = None
        self.y: C = None
        self.u: I = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.z: H = None
        self.o: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: G = None
        self.t: E = None
        self.w: F = None
        self.z: E = None
        self.u: C = None
        self.o: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.o: B = None
        self.w: E = None
        self.s: F = None
        self.x: H = None
        self.y: B = None
        self.u: C = None
        self.p: H = None
        self.r: D = None
        self.txt = txt

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

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