class A:
    def __init__(self, txt: str):
        self.v: F = None
        self.u: B = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.p: F = None
        self.y: G = None
        self.v: F = None
        self.u: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: B = None
        self.p: C = None
        self.z: C = None
        self.s: G = None
        self.v: F = None
        self.x: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: F = None
        self.z: B = None
        self.y: B = None
        self.txt = txt

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.p: F = None
        self.y: G = None
        self.v: F = None
        self.u: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: B = None
        self.p: C = None
        self.z: C = None
        self.s: G = None
        self.v: F = None
        self.x: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: F = None
        self.z: B = None
        self.y: B = None
        self.txt = txt

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

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

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