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

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

class C:
    def __init__(self, txt: str):
        self.z: B = None
        self.x: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: I = None
        self.q: A = None
        self.x: B = None
        self.w: J = None
        self.p: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: G = None
        self.u: A = None
        self.y: C = None
        self.w: A = None
        self.p: H = None
        self.q: B = None
        self.v: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: C = None
        self.t: I = None
        self.y: D = None
        self.w: J = None
        self.p: G = None
        self.q: A = None
        self.r: G = None
        self.s: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.x: D = None
        self.u: I = None
        self.s: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: C = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.y: C = None
        self.z: G = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.z: B = None
        self.x: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: I = None
        self.q: A = None
        self.x: B = None
        self.w: J = None
        self.p: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: G = None
        self.u: A = None
        self.y: C = None
        self.w: A = None
        self.p: H = None
        self.q: B = None
        self.v: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: C = None
        self.t: I = None
        self.y: D = None
        self.w: J = None
        self.p: G = None
        self.q: A = None
        self.r: G = None
        self.s: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.x: D = None
        self.u: I = None
        self.s: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: C = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.y: C = None
        self.z: G = None
        self.txt = txt

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

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