class A:
    def __init__(self, txt: str):
        self.z: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.p: I = None
        self.o: E = None
        self.w: J = None
        self.v: J = None
        self.u: G = None
        self.z: G = None
        self.t: J = None
        self.y: J = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.q: F = None
        self.s: H = None
        self.t: I = None
        self.w: I = None
        self.z: J = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.x: J = None
        self.q: B = None
        self.u: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: A = None
        self.o: D = None
        self.p: B = None
        self.v: G = None
        self.x: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: B = None
        self.o: A = None
        self.z: C = None
        self.x: E = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.w: E = None
        self.s: D = None
        self.x: J = None
        self.p: D = None
        self.y: F = None
        self.v: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.t: D = None
        self.q: A = None
        self.x: C = None
        self.s: D = None
        self.r: B = None
        self.u: F = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.p: I = None
        self.o: E = None
        self.w: J = None
        self.v: J = None
        self.u: G = None
        self.z: G = None
        self.t: J = None
        self.y: J = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.q: F = None
        self.s: H = None
        self.t: I = None
        self.w: I = None
        self.z: J = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.x: J = None
        self.q: B = None
        self.u: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: A = None
        self.o: D = None
        self.p: B = None
        self.v: G = None
        self.x: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: B = None
        self.o: A = None
        self.z: C = None
        self.x: E = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.w: E = None
        self.s: D = None
        self.x: J = None
        self.p: D = None
        self.y: F = None
        self.v: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.t: D = None
        self.q: A = None
        self.x: C = None
        self.s: D = None
        self.r: B = None
        self.u: F = None
        self.txt = txt

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

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