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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.o: E = None
        self.q: C = None
        self.w: D = None
        self.v: D = None
        self.t: C = None
        self.x: H = None
        self.z: G = None
        self.u: J = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.v: E = None
        self.o: E = None
        self.r: A = None
        self.u: C = None
        self.t: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.o: A = None
        self.z: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.p: H = None
        self.t: I = None
        self.v: B = None
        self.s: H = None
        self.txt = txt

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

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.o: E = None
        self.q: C = None
        self.w: D = None
        self.v: D = None
        self.t: C = None
        self.x: H = None
        self.z: G = None
        self.u: J = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.v: E = None
        self.o: E = None
        self.r: A = None
        self.u: C = None
        self.t: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.o: A = None
        self.z: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.p: H = None
        self.t: I = None
        self.v: B = None
        self.s: H = None
        self.txt = txt

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

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