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

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

class C:
    def __init__(self, txt: str):
        self.w: D = None
        self.o: B = None
        self.q: H = None
        self.t: H = None
        self.p: E = None
        self.r: H = None
        self.txt = txt

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

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.w: E = None
        self.o: C = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.w: D = None
        self.o: B = None
        self.q: H = None
        self.t: H = None
        self.p: E = None
        self.r: H = None
        self.txt = txt

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

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.w: E = None
        self.o: C = None
        self.txt = txt

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

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