class A:
    def __init__(self, txt: str):
        self.s: E = None
        self.y: G = None
        self.z: H = None
        self.v: G = None
        self.p: D = None
        self.q: F = None
        self.u: F = None
        self.w: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.r: G = None
        self.t: C = None
        self.s: F = None
        self.o: F = None
        self.x: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: I = None
        self.r: I = None
        self.x: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.u: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: D = None
        self.q: E = None
        self.w: E = None
        self.s: E = None
        self.u: A = None
        self.o: B = None
        self.p: B = None
        self.r: I = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.p: D = None
        self.x: A = None
        self.v: D = None
        self.z: B = None
        self.y: D = None
        self.t: C = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.r: G = None
        self.t: C = None
        self.s: F = None
        self.o: F = None
        self.x: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: I = None
        self.r: I = None
        self.x: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.u: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: D = None
        self.q: E = None
        self.w: E = None
        self.s: E = None
        self.u: A = None
        self.o: B = None
        self.p: B = None
        self.r: I = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.p: D = None
        self.x: A = None
        self.v: D = None
        self.z: B = None
        self.y: D = None
        self.t: C = None
        self.txt = txt

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

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