class A:
    def __init__(self, txt: str):
        self.z: G = None
        self.v: F = None
        self.p: J = None
        self.u: J = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: H = None
        self.z: F = None
        self.v: E = None
        self.t: A = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.y: H = None
        self.r: H = None
        self.u: B = None
        self.v: J = None
        self.q: H = None
        self.w: A = None
        self.t: F = None
        self.x: J = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: F = None
        self.u: J = None
        self.q: F = None
        self.x: H = None
        self.r: I = None
        self.t: J = None
        self.s: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.o: D = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.x: H = None
        self.z: F = None
        self.v: E = None
        self.t: A = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.y: H = None
        self.r: H = None
        self.u: B = None
        self.v: J = None
        self.q: H = None
        self.w: A = None
        self.t: F = None
        self.x: J = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: F = None
        self.u: J = None
        self.q: F = None
        self.x: H = None
        self.r: I = None
        self.t: J = None
        self.s: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.o: D = None
        self.txt = txt

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

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

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