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

class B:
    def __init__(self, txt: str):
        self.r: D = None
        self.t: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: I = None
        self.q: F = None
        self.v: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: E = None
        self.o: C = None
        self.s: B = None
        self.z: I = None
        self.w: I = None
        self.v: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: A = None
        self.v: I = None
        self.x: H = None
        self.p: J = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.s: J = None
        self.y: E = None
        self.o: E = None
        self.q: I = None
        self.v: G = None
        self.p: G = None
        self.x: D = None
        self.t: J = None
        self.r: A = None
        self.w: J = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.y: D = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.r: D = None
        self.t: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: I = None
        self.q: F = None
        self.v: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: E = None
        self.o: C = None
        self.s: B = None
        self.z: I = None
        self.w: I = None
        self.v: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: A = None
        self.v: I = None
        self.x: H = None
        self.p: J = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.s: J = None
        self.y: E = None
        self.o: E = None
        self.q: I = None
        self.v: G = None
        self.p: G = None
        self.x: D = None
        self.t: J = None
        self.r: A = None
        self.w: J = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.y: D = None
        self.txt = txt

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

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