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

class B:
    def __init__(self, txt: str):
        self.q: H = None
        self.z: A = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.y: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.v: H = None
        self.p: E = None
        self.q: G = None
        self.o: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: H = None
        self.s: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.t: G = None
        self.s: D = None
        self.r: G = None
        self.o: G = None
        self.v: D = None
        self.w: B = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.q: H = None
        self.z: A = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.y: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.v: H = None
        self.p: E = None
        self.q: G = None
        self.o: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: H = None
        self.s: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.t: G = None
        self.s: D = None
        self.r: G = None
        self.o: G = None
        self.v: D = None
        self.w: B = None
        self.txt = txt

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

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