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

class B:
    def __init__(self, txt: str):
        self.q: I = None
        self.t: G = None
        self.z: D = None
        self.y: E = None
        self.r: E = None
        self.w: F = None
        self.o: E = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.p: D = None
        self.u: C = None
        self.s: I = None
        self.w: H = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.o: B = None
        self.u: G = None
        self.t: I = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.q: I = None
        self.t: G = None
        self.z: D = None
        self.y: E = None
        self.r: E = None
        self.w: F = None
        self.o: E = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.p: D = None
        self.u: C = None
        self.s: I = None
        self.w: H = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.o: B = None
        self.u: G = None
        self.t: I = None
        self.txt = txt

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

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

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