class A:
    def __init__(self, txt: str):
        self.t: I = None
        self.v: B = None
        self.q: H = None
        self.x: D = None
        self.z: I = None
        self.r: C = None
        self.y: J = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: G = None
        self.x: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.q: E = None
        self.t: F = None
        self.s: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.w: A = None
        self.x: J = None
        self.t: A = None
        self.s: I = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.r: F = None
        self.u: C = None
        self.v: I = None
        self.w: J = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.o: G = None
        self.u: G = None
        self.x: F = None
        self.w: H = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.v: G = None
        self.x: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.q: E = None
        self.t: F = None
        self.s: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.w: A = None
        self.x: J = None
        self.t: A = None
        self.s: I = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.r: F = None
        self.u: C = None
        self.v: I = None
        self.w: J = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.o: G = None
        self.u: G = None
        self.x: F = None
        self.w: H = None
        self.txt = txt

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

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