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

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

class C:
    def __init__(self, txt: str):
        self.p: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.u: C = None
        self.q: B = None
        self.p: H = None
        self.y: B = None
        self.w: I = None
        self.t: I = None
        self.s: I = None
        self.x: I = None
        self.v: H = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.y: C = None
        self.s: A = None
        self.v: F = None
        self.w: F = None
        self.x: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: B = None
        self.p: E = None
        self.t: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: H = None
        self.w: E = None
        self.p: D = None
        self.s: A = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.p: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.u: C = None
        self.q: B = None
        self.p: H = None
        self.y: B = None
        self.w: I = None
        self.t: I = None
        self.s: I = None
        self.x: I = None
        self.v: H = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.y: C = None
        self.s: A = None
        self.v: F = None
        self.w: F = None
        self.x: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: B = None
        self.p: E = None
        self.t: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: H = None
        self.w: E = None
        self.p: D = None
        self.s: A = None
        self.txt = txt

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

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