class A:
    def __init__(self, txt: str):
        self.v: D = None
        self.o: G = None
        self.s: E = None
        self.z: I = None
        self.u: G = None
        self.q: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: F = None
        self.y: A = None
        self.r: I = None
        self.w: C = None
        self.o: C = None
        self.u: C = None
        self.z: H = None
        self.v: H = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.q: B = None
        self.x: B = None
        self.o: F = None
        self.u: A = None
        self.r: E = None
        self.y: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: G = None
        self.y: I = None
        self.o: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: I = None
        self.y: C = None
        self.t: H = None
        self.r: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: B = None
        self.q: I = None
        self.w: H = None
        self.o: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: A = None
        self.s: A = None
        self.y: G = None
        self.u: I = None
        self.x: F = None
        self.o: B = None
        self.w: A = None
        self.txt = txt

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

n = A("n")
l = B("l")
j = C("j")
i = D("i")
m = E("m")
a = F("a")
c = G("c")
h = H("h")
k = I("k")

n.v = i
n.o = c
n.u = c
n.s = m
n.z = k
n.q = j
l.s = a
l.y = n
l.r = k
l.w = j
l.o = j
l.u = j
l.z = h
l.v = h
j.y = k
j.z = k
j.s = k
j.r = c
j.u = m
j.t = i
j.q = a
j.o = h
j.v = h
i.q = l
i.x = l
i.o = a
i.u = n
i.y = n
i.r = m
m.t = c
m.y = k
m.o = n
a.s = k
a.y = j
a.t = h
a.r = i
c.y = l
c.o = l
c.q = k
c.w = h
h.q = n
h.s = n
h.w = n
h.y = c
h.u = k
h.x = a
h.o = l
k.r = i
k.z = n
assert n.u.o.u.z.txt == "
class A:
    def __init__(self, txt: str):
        self.v: D = None
        self.o: G = None
        self.s: E = None
        self.z: I = None
        self.u: G = None
        self.q: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: F = None
        self.y: A = None
        self.r: I = None
        self.w: C = None
        self.o: C = None
        self.u: C = None
        self.z: H = None
        self.v: H = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.q: B = None
        self.x: B = None
        self.o: F = None
        self.u: A = None
        self.r: E = None
        self.y: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: G = None
        self.y: I = None
        self.o: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: I = None
        self.y: C = None
        self.t: H = None
        self.r: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: B = None
        self.q: I = None
        self.w: H = None
        self.o: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: A = None
        self.s: A = None
        self.y: G = None
        self.u: I = None
        self.x: F = None
        self.o: B = None
        self.w: A = None
        self.txt = txt

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

n = A("n")
l = B("l")
j = C("j")
i = D("i")
m = E("m")
a = F("a")
c = G("c")
h = H("h")
k = I("k")

n.v = i
n.o = c
n.u = c
n.s = m
n.z = k
n.q = j
l.s = a
l.y = n
l.r = k
l.w = j
l.o = j
l.u = j
l.z = h
l.v = h
j.y = k
j.z = k
j.s = k
j.r = c
j.u = m
j.t = i
j.q = a
j.o = h
j.v = h
i.q = l
i.x = l
i.o = a
i.u = n
i.y = n
i.r = m
m.t = c
m.y = k
m.o = n
a.s = k
a.y = j
a.t = h
a.r = i
c.y = l
c.o = l
c.q = k
c.w = h
h.q = n
h.s = n
h.w = n
h.y = c
h.u = k
h.x = a
h.o = l
k.r = i
k.z = n
assert n.u.o.u.z.txt == "k"