class A:
    def __init__(self, txt: str):
        self.v: B = None
        self.q: D = None
        self.s: C = None
        self.z: C = None
        self.p: I = None
        self.r: G = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.v: G = None
        self.r: A = None
        self.o: E = None
        self.q: I = None
        self.p: G = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.u: A = None
        self.s: C = None
        self.y: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: B = None
        self.z: D = None
        self.q: J = None
        self.t: E = None
        self.txt = txt

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

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.v: G = None
        self.r: A = None
        self.o: E = None
        self.q: I = None
        self.p: G = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.u: A = None
        self.s: C = None
        self.y: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: B = None
        self.z: D = None
        self.q: J = None
        self.t: E = None
        self.txt = txt

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

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

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

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