class A:
    def __init__(self, txt: str):
        self.z: E = None
        self.u: B = None
        self.y: E = None
        self.t: D = None
        self.r: B = None
        self.s: C = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.v: B = None
        self.w: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: G = None
        self.q: B = None
        self.v: G = None
        self.x: F = None
        self.r: A = None
        self.w: A = None
        self.s: G = None
        self.p: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: D = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.s: J = None
        self.q: H = None
        self.z: D = None
        self.r: I = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.x: H = None
        self.r: F = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.v: B = None
        self.w: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: G = None
        self.q: B = None
        self.v: G = None
        self.x: F = None
        self.r: A = None
        self.w: A = None
        self.s: G = None
        self.p: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: D = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.s: J = None
        self.q: H = None
        self.z: D = None
        self.r: I = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.x: H = None
        self.r: F = None
        self.txt = txt

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

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

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