class A:
    def __init__(self, txt: str):
        self.x: J = None
        self.o: J = None
        self.v: F = None
        self.u: I = None
        self.s: B = None
        self.r: J = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: H = None
        self.v: D = None
        self.r: E = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.q: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.w: J = None
        self.p: E = None
        self.r: J = None
        self.s: H = None
        self.t: H = None
        self.y: I = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.p: C = None
        self.s: C = None
        self.y: E = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: G = None
        self.p: D = None
        self.x: D = None
        self.t: D = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.u: C = None
        self.v: C = None
        self.x: D = None
        self.p: D = None
        self.r: B = None
        self.q: B = None
        self.w: C = None
        self.o: I = None
        self.t: B = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.o: H = None
        self.v: D = None
        self.r: E = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.q: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.w: J = None
        self.p: E = None
        self.r: J = None
        self.s: H = None
        self.t: H = None
        self.y: I = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.p: C = None
        self.s: C = None
        self.y: E = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: G = None
        self.p: D = None
        self.x: D = None
        self.t: D = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.u: C = None
        self.v: C = None
        self.x: D = None
        self.p: D = None
        self.r: B = None
        self.q: B = None
        self.w: C = None
        self.o: I = None
        self.t: B = None
        self.txt = txt

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

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