class A:
    def __init__(self, txt: str):
        self.o: I = None
        self.y: B = None
        self.p: D = None
        self.q: F = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.t: J = None
        self.r: D = None
        self.p: A = None
        self.u: F = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.t: H = None
        self.p: A = None
        self.s: J = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: E = None
        self.q: A = None
        self.x: C = None
        self.y: G = None
        self.o: J = None
        self.u: E = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.z: G = None
        self.o: G = None
        self.y: C = None
        self.v: F = None
        self.u: I = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.t: J = None
        self.r: D = None
        self.p: A = None
        self.u: F = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.t: H = None
        self.p: A = None
        self.s: J = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: E = None
        self.q: A = None
        self.x: C = None
        self.y: G = None
        self.o: J = None
        self.u: E = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.z: G = None
        self.o: G = None
        self.y: C = None
        self.v: F = None
        self.u: I = None
        self.txt = txt

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

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