class A:
    def __init__(self, txt: str):
        self.v: B = None
        self.s: B = None
        self.o: H = None
        self.y: I = None
        self.t: H = None
        self.u: D = None
        self.z: D = None
        self.p: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: D = None
        self.o: I = None
        self.t: G = None
        self.v: E = None
        self.r: D = None
        self.x: C = None
        self.y: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: G = None
        self.u: E = None
        self.x: G = None
        self.p: I = None
        self.z: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: I = None
        self.r: I = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.r: A = None
        self.t: F = None
        self.q: C = None
        self.y: F = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.u: H = None
        self.z: D = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.z: D = None
        self.o: I = None
        self.t: G = None
        self.v: E = None
        self.r: D = None
        self.x: C = None
        self.y: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: G = None
        self.u: E = None
        self.x: G = None
        self.p: I = None
        self.z: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: I = None
        self.r: I = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.r: A = None
        self.t: F = None
        self.q: C = None
        self.y: F = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.u: H = None
        self.z: D = None
        self.txt = txt

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

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