class A:
    def __init__(self, txt: str):
        self.t: H = None
        self.s: H = None
        self.u: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: A = None
        self.s: F = None
        self.q: F = None
        self.p: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: A = None
        self.q: E = None
        self.z: E = None
        self.t: G = None
        self.v: G = None
        self.x: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: A = None
        self.p: C = None
        self.x: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: G = None
        self.v: F = None
        self.txt = txt

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.o: A = None
        self.s: F = None
        self.q: F = None
        self.p: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: A = None
        self.q: E = None
        self.z: E = None
        self.t: G = None
        self.v: G = None
        self.x: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: A = None
        self.p: C = None
        self.x: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: G = None
        self.v: F = None
        self.txt = txt

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

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

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

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

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