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

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

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

class D:
    def __init__(self, txt: str):
        self.q: H = None
        self.t: B = None
        self.r: H = None
        self.z: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: D = None
        self.x: F = None
        self.v: A = None
        self.t: A = None
        self.r: C = None
        self.q: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: A = None
        self.t: B = None
        self.z: G = None
        self.p: I = None
        self.u: E = None
        self.s: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: A = None
        self.p: E = None
        self.q: H = None
        self.z: A = None
        self.t: A = None
        self.x: D = None
        self.w: I = None
        self.o: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.p: B = None
        self.s: G = None
        self.o: C = None
        self.r: E = None
        self.t: G = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.q: H = None
        self.t: B = None
        self.r: H = None
        self.z: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: D = None
        self.x: F = None
        self.v: A = None
        self.t: A = None
        self.r: C = None
        self.q: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: A = None
        self.t: B = None
        self.z: G = None
        self.p: I = None
        self.u: E = None
        self.s: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: A = None
        self.p: E = None
        self.q: H = None
        self.z: A = None
        self.t: A = None
        self.x: D = None
        self.w: I = None
        self.o: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.p: B = None
        self.s: G = None
        self.o: C = None
        self.r: E = None
        self.t: G = None
        self.txt = txt

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

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