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

class B:
    def __init__(self, txt: str):
        self.y: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: I = None
        self.o: G = None
        self.t: G = None
        self.z: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: D = None
        self.q: H = None
        self.w: F = None
        self.p: C = None
        self.u: A = None
        self.r: H = None
        self.v: C = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.x: A = None
        self.s: D = None
        self.o: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.r: C = None
        self.z: B = None
        self.s: G = None
        self.w: D = None
        self.txt = txt

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

j = A("j")
l = B("l")
g = C("g")
h = D("h")
a = E("a")
e = F("e")
f = G("f")
k = H("k")
c = I("c")
n = J("n")

j.t = g
j.r = h
j.z = e
j.w = e
j.o = f
j.u = a
j.v = a
j.p = l
j.x = k
j.y = k
l.y = j
g.x = c
g.o = f
g.t = f
g.z = e
h.p = g
h.u = j
h.r = l
h.q = l
h.t = k
a.t = h
a.q = k
a.r = k
a.w = e
a.p = g
a.v = g
a.u = j
e.s = n
e.w = a
e.y = a
e.q = g
e.z = l
e.p = h
e.r = f
f.y = a
f.x = a
f.s = l
f.q = l
f.p = l
f.z = e
f.w = h
f.u = h
f.o = g
f.v = k
k.x = j
k.s = h
k.o = e
c.r = g
c.z = l
c.s = f
c.w = h
n.q = e
n.x = f
n.t = j
assert k.s.q.y.r.t.txt == "
class A:
    def __init__(self, txt: str):
        self.t: C = None
        self.r: D = None
        self.z: F = None
        self.w: F = None
        self.o: G = None
        self.u: E = None
        self.p: B = None
        self.x: H = None
        self.y: H = None
        self.v: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: I = None
        self.o: G = None
        self.t: G = None
        self.z: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: D = None
        self.q: H = None
        self.w: F = None
        self.p: C = None
        self.u: A = None
        self.r: H = None
        self.v: C = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.x: A = None
        self.s: D = None
        self.o: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.r: C = None
        self.z: B = None
        self.s: G = None
        self.w: D = None
        self.txt = txt

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

j = A("j")
l = B("l")
g = C("g")
h = D("h")
a = E("a")
e = F("e")
f = G("f")
k = H("k")
c = I("c")
n = J("n")

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