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

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

class C:
    def __init__(self, txt: str):
        self.t: A = None
        self.z: E = None
        self.x: D = None
        self.u: J = None
        self.s: A = None
        self.q: G = None
        self.w: J = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: E = None
        self.w: F = None
        self.p: C = None
        self.z: I = None
        self.q: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: J = None
        self.z: H = None
        self.x: C = None
        self.r: B = None
        self.s: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: A = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.z: J = None
        self.s: D = None
        self.y: J = None
        self.r: F = None
        self.p: C = None
        self.o: E = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.o: G = None
        self.t: E = None
        self.r: F = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.t: A = None
        self.z: E = None
        self.x: D = None
        self.u: J = None
        self.s: A = None
        self.q: G = None
        self.w: J = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: E = None
        self.w: F = None
        self.p: C = None
        self.z: I = None
        self.q: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: J = None
        self.z: H = None
        self.x: C = None
        self.r: B = None
        self.s: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: A = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.z: J = None
        self.s: D = None
        self.y: J = None
        self.r: F = None
        self.p: C = None
        self.o: E = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.o: G = None
        self.t: E = None
        self.r: F = None
        self.txt = txt

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

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