class A:
    def __init__(self, txt: str):
        self.o: J = None
        self.q: D = None
        self.u: H = None
        self.s: H = None
        self.p: G = None
        self.x: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: I = None
        self.q: I = None
        self.v: J = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: D = None
        self.r: G = None
        self.t: E = None
        self.z: I = None
        self.q: I = None
        self.s: G = None
        self.w: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: B = None
        self.z: H = None
        self.o: A = None
        self.s: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: B = None
        self.p: B = None
        self.u: A = None
        self.w: J = None
        self.s: J = None
        self.o: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: G = None
        self.p: J = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.v: G = None
        self.t: G = None
        self.s: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.y: J = None
        self.v: A = None
        self.p: H = None
        self.t: J = None
        self.z: C = None
        self.u: B = None
        self.q: H = None
        self.r: B = None
        self.s: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.o: E = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.u: I = None
        self.q: I = None
        self.v: J = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: D = None
        self.r: G = None
        self.t: E = None
        self.z: I = None
        self.q: I = None
        self.s: G = None
        self.w: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: B = None
        self.z: H = None
        self.o: A = None
        self.s: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: B = None
        self.p: B = None
        self.u: A = None
        self.w: J = None
        self.s: J = None
        self.o: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: G = None
        self.p: J = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.v: G = None
        self.t: G = None
        self.s: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.y: J = None
        self.v: A = None
        self.p: H = None
        self.t: J = None
        self.z: C = None
        self.u: B = None
        self.q: H = None
        self.r: B = None
        self.s: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.o: E = None
        self.txt = txt

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

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