class A:
    def __init__(self, txt: str):
        self.z: B = None
        self.s: B = None
        self.t: A = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: F = None
        self.p: A = None
        self.y: D = None
        self.w: E = None
        self.u: A = None
        self.v: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: H = None
        self.s: A = None
        self.w: C = None
        self.t: H = None
        self.q: B = None
        self.txt = txt

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.o: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: F = None
        self.p: A = None
        self.y: D = None
        self.w: E = None
        self.u: A = None
        self.v: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: H = None
        self.s: A = None
        self.w: C = None
        self.t: H = None
        self.q: B = None
        self.txt = txt

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

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

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

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

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