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

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

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

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

class E:
    def __init__(self, txt: str):
        self.p: G = None
        self.z: H = None
        self.u: F = None
        self.x: H = None
        self.o: D = None
        self.w: F = None
        self.v: F = None
        self.t: G = None
        self.q: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: E = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.x: C = None
        self.q: F = None
        self.p: E = None
        self.w: E = None
        self.r: H = None
        self.o: H = None
        self.z: E = None
        self.v: B = None
        self.y: E = None
        self.txt = txt

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

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.p: G = None
        self.z: H = None
        self.u: F = None
        self.x: H = None
        self.o: D = None
        self.w: F = None
        self.v: F = None
        self.t: G = None
        self.q: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: E = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.x: C = None
        self.q: F = None
        self.p: E = None
        self.w: E = None
        self.r: H = None
        self.o: H = None
        self.z: E = None
        self.v: B = None
        self.y: E = None
        self.txt = txt

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

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