class A:
    def __init__(self, txt: str):
        self.z: B = None
        self.s: D = None
        self.w: I = None
        self.u: I = None
        self.o: B = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.z: I = None
        self.y: H = None
        self.s: C = None
        self.r: F = None
        self.t: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: D = None
        self.z: J = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.p: J = None
        self.t: A = None
        self.u: H = None
        self.y: C = None
        self.z: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.q: G = None
        self.s: G = None
        self.p: E = None
        self.t: H = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.z: I = None
        self.y: H = None
        self.s: C = None
        self.r: F = None
        self.t: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: D = None
        self.z: J = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.p: J = None
        self.t: A = None
        self.u: H = None
        self.y: C = None
        self.z: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.q: G = None
        self.s: G = None
        self.p: E = None
        self.t: H = None
        self.txt = txt

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

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