class A:
    def __init__(self, txt: str):
        self.s: F = None
        self.x: C = None
        self.z: J = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.t: G = None
        self.s: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.v: G = None
        self.w: G = None
        self.z: I = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.u: J = None
        self.q: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: J = None
        self.u: F = None
        self.r: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: A = None
        self.z: A = None
        self.s: J = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.o: F = None
        self.y: B = None
        self.t: A = None
        self.r: D = None
        self.v: C = None
        self.txt = txt

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

b.s = i
b.x = l
b.z = k
e.t = a
e.s = a
l.t = b
l.s = g
l.x = i
l.q = i
l.y = i
l.p = j
l.u = f
l.z = a
l.w = h
j.v = a
j.w = a
j.z = h
g.o = k
g.y = k
g.u = k
g.s = l
g.r = i
g.p = i
g.z = f
g.t = j
g.x = a
i.u = k
i.q = h
a.v = k
a.u = i
a.r = j
f.p = b
h.q = b
h.z = b
h.s = k
k.o = i
k.y = e
k.t = b
k.r = j
k.v = l
assert f.p.z.y.t.v.t.x.z.r.z.txt == "
class A:
    def __init__(self, txt: str):
        self.s: F = None
        self.x: C = None
        self.z: J = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.t: G = None
        self.s: G = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.v: G = None
        self.w: G = None
        self.z: I = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.u: J = None
        self.q: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: J = None
        self.u: F = None
        self.r: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: A = None
        self.z: A = None
        self.s: J = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.o: F = None
        self.y: B = None
        self.t: A = None
        self.r: D = None
        self.v: C = None
        self.txt = txt

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

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