class A:
    def __init__(self, txt: str):
        self.t: D = None
        self.p: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: J = None
        self.p: I = None
        self.v: F = None
        self.o: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: J = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.r: A = None
        self.v: H = None
        self.s: J = None
        self.y: B = None
        self.w: I = None
        self.z: A = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.z: H = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.t: H = None
        self.x: F = None
        self.z: C = None
        self.v: I = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.x: J = None
        self.p: I = None
        self.v: F = None
        self.o: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: J = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.r: A = None
        self.v: H = None
        self.s: J = None
        self.y: B = None
        self.w: I = None
        self.z: A = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.z: H = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.t: H = None
        self.x: F = None
        self.z: C = None
        self.v: I = None
        self.txt = txt

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

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