class A:
    def __init__(self, txt: str):
        self.t: D = None
        self.u: A = None
        self.v: D = None
        self.x: C = None
        self.s: F = None
        self.r: H = None
        self.q: C = None
        self.z: A = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.w: E = None
        self.z: H = None
        self.s: F = None
        self.p: A = None
        self.r: G = None
        self.y: C = None
        self.o: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: F = None
        self.p: F = None
        self.o: A = None
        self.y: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: C = None
        self.x: C = None
        self.t: C = None
        self.y: E = None
        self.q: H = None
        self.v: B = None
        self.s: E = None
        self.u: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: D = None
        self.u: D = None
        self.t: H = None
        self.o: D = None
        self.w: G = None
        self.p: H = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.w: E = None
        self.z: H = None
        self.s: F = None
        self.p: A = None
        self.r: G = None
        self.y: C = None
        self.o: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.q: F = None
        self.p: F = None
        self.o: A = None
        self.y: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: C = None
        self.x: C = None
        self.t: C = None
        self.y: E = None
        self.q: H = None
        self.v: B = None
        self.s: E = None
        self.u: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: D = None
        self.u: D = None
        self.t: H = None
        self.o: D = None
        self.w: G = None
        self.p: H = None
        self.txt = txt

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

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