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

class B:
    def __init__(self, txt: str):
        self.v: G = None
        self.x: J = None
        self.y: J = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.v: B = None
        self.o: F = None
        self.x: A = None
        self.z: G = None
        self.y: G = None
        self.w: F = None
        self.t: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: E = None
        self.z: A = None
        self.y: E = None
        self.p: I = None
        self.x: I = None
        self.w: I = None
        self.v: G = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.w: D = None
        self.p: I = None
        self.t: I = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.w: B = None
        self.u: G = None
        self.x: A = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.v: G = None
        self.x: J = None
        self.y: J = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.v: B = None
        self.o: F = None
        self.x: A = None
        self.z: G = None
        self.y: G = None
        self.w: F = None
        self.t: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: E = None
        self.z: A = None
        self.y: E = None
        self.p: I = None
        self.x: I = None
        self.w: I = None
        self.v: G = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.w: D = None
        self.p: I = None
        self.t: I = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.w: B = None
        self.u: G = None
        self.x: A = None
        self.txt = txt

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

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