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

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

class C:
    def __init__(self, txt: str):
        self.y: A = None
        self.u: J = None
        self.r: H = None
        self.x: G = None
        self.v: J = None
        self.q: J = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: E = None
        self.z: H = None
        self.x: C = None
        self.q: A = None
        self.p: I = None
        self.v: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.o: C = None
        self.p: F = None
        self.s: H = None
        self.v: J = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: J = None
        self.p: E = None
        self.u: D = None
        self.y: B = None
        self.q: B = None
        self.w: B = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.u: B = None
        self.t: J = None
        self.q: E = None
        self.r: G = None
        self.z: J = None
        self.x: B = None
        self.w: B = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.w: G = None
        self.s: G = None
        self.u: H = None
        self.p: H = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.y: A = None
        self.u: J = None
        self.r: H = None
        self.x: G = None
        self.v: J = None
        self.q: J = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: E = None
        self.z: H = None
        self.x: C = None
        self.q: A = None
        self.p: I = None
        self.v: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.o: C = None
        self.p: F = None
        self.s: H = None
        self.v: J = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: J = None
        self.p: E = None
        self.u: D = None
        self.y: B = None
        self.q: B = None
        self.w: B = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.u: B = None
        self.t: J = None
        self.q: E = None
        self.r: G = None
        self.z: J = None
        self.x: B = None
        self.w: B = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.w: G = None
        self.s: G = None
        self.u: H = None
        self.p: H = None
        self.txt = txt

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

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