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

class B:
    def __init__(self, txt: str):
        self.q: D = None
        self.y: F = None
        self.o: A = None
        self.u: F = None
        self.t: A = None
        self.s: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: G = None
        self.r: A = None
        self.x: H = None
        self.s: B = None
        self.t: A = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.u: E = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.q: D = None
        self.y: F = None
        self.o: A = None
        self.u: F = None
        self.t: A = None
        self.s: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: G = None
        self.r: A = None
        self.x: H = None
        self.s: B = None
        self.t: A = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.u: E = None
        self.txt = txt

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

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

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