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

class B:
    def __init__(self, txt: str):
        self.u: C = None
        self.z: C = None
        self.q: D = None
        self.w: A = None
        self.r: D = None
        self.p: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.w: G = None
        self.r: G = None
        self.x: E = None
        self.v: A = None
        self.o: H = None
        self.s: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: G = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.w: A = None
        self.t: E = None
        self.v: F = None
        self.z: E = None
        self.y: F = None
        self.p: A = None
        self.q: A = None
        self.r: F = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.u: C = None
        self.z: C = None
        self.q: D = None
        self.w: A = None
        self.r: D = None
        self.p: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.w: G = None
        self.r: G = None
        self.x: E = None
        self.v: A = None
        self.o: H = None
        self.s: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: G = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.w: A = None
        self.t: E = None
        self.v: F = None
        self.z: E = None
        self.y: F = None
        self.p: A = None
        self.q: A = None
        self.r: F = None
        self.txt = txt

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

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