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

class B:
    def __init__(self, txt: str):
        self.x: C = None
        self.q: I = None
        self.r: D = None
        self.o: J = None
        self.u: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: F = None
        self.s: D = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.r: A = None
        self.o: B = None
        self.p: B = None
        self.t: J = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.s: E = None
        self.t: A = None
        self.o: J = None
        self.y: I = None
        self.p: C = None
        self.x: G = None
        self.z: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: J = None
        self.t: C = None
        self.q: G = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.y: G = None
        self.o: D = None
        self.z: D = None
        self.s: H = None
        self.t: G = None
        self.u: F = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.x: C = None
        self.q: I = None
        self.r: D = None
        self.o: J = None
        self.u: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: F = None
        self.s: D = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.r: A = None
        self.o: B = None
        self.p: B = None
        self.t: J = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.s: E = None
        self.t: A = None
        self.o: J = None
        self.y: I = None
        self.p: C = None
        self.x: G = None
        self.z: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: J = None
        self.t: C = None
        self.q: G = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.y: G = None
        self.o: D = None
        self.z: D = None
        self.s: H = None
        self.t: G = None
        self.u: F = None
        self.txt = txt

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

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