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

class B:
    def __init__(self, txt: str):
        self.v: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: F = None
        self.y: C = None
        self.z: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: A = None
        self.s: C = None
        self.r: C = None
        self.x: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: D = None
        self.r: E = None
        self.p: E = None
        self.y: D = None
        self.z: A = None
        self.w: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: B = None
        self.o: C = None
        self.u: C = None
        self.p: D = None
        self.t: E = None
        self.w: B = None
        self.txt = txt

a = A("a")
m = B("m")
e = C("e")
g = D("g")
f = E("f")
j = F("j")
h = A("h")
k = C("k")
b = E("b")

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

class B:
    def __init__(self, txt: str):
        self.v: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: F = None
        self.y: C = None
        self.z: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: A = None
        self.s: C = None
        self.r: C = None
        self.x: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: D = None
        self.r: E = None
        self.p: E = None
        self.y: D = None
        self.z: A = None
        self.w: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: B = None
        self.o: C = None
        self.u: C = None
        self.p: D = None
        self.t: E = None
        self.w: B = None
        self.txt = txt

a = A("a")
m = B("m")
e = C("e")
g = D("g")
f = E("f")
j = F("j")
h = A("h")
k = C("k")
b = E("b")

a.s = g
m.v = j
e.x = j
e.y = k
e.z = m
g.y = a
g.s = k
g.r = k
g.x = j
f.u = g
f.y = g
f.r = b
f.p = b
f.z = h
f.w = k
j.r = m
j.w = m
j.o = e
j.u = k
j.p = g
j.t = b
h.s = g
k.x = j
k.y = e
k.z = m
b.u = g
b.y = g
b.r = f
b.p = f
b.z = a
b.w = e
assert a.s.s.x.t.z.txt == "a"