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

class B:
    def __init__(self, txt: str):
        self.s: E = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: B = None
        self.v: A = None
        self.w: B = None
        self.z: E = None
        self.x: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.o: D = None
        self.s: A = None
        self.x: B = None
        self.z: B = None
        self.txt = txt

j = A("j")
b = B("b")
n = C("n")
d = D("d")
i = E("i")
a = A("a")
f = E("f")
l = D("l")

j.z = a
j.w = b
j.x = n
b.s = i
n.x = i
d.s = b
d.w = b
d.v = j
d.z = f
d.x = f
i.o = d
i.s = j
i.x = b
i.z = b
a.z = j
a.w = b
a.x = n
f.o = l
f.s = a
f.x = b
f.z = b
l.s = b
l.w = b
l.v = j
l.z = f
l.x = i
assert l.v.x.x.o.z.z.txt == "
class A:
    def __init__(self, txt: str):
        self.z: A = None
        self.w: B = None
        self.x: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: E = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: B = None
        self.v: A = None
        self.w: B = None
        self.z: E = None
        self.x: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.o: D = None
        self.s: A = None
        self.x: B = None
        self.z: B = None
        self.txt = txt

j = A("j")
b = B("b")
n = C("n")
d = D("d")
i = E("i")
a = A("a")
f = E("f")
l = D("l")

j.z = a
j.w = b
j.x = n
b.s = i
n.x = i
d.s = b
d.w = b
d.v = j
d.z = f
d.x = f
i.o = d
i.s = j
i.x = b
i.z = b
a.z = j
a.w = b
a.x = n
f.o = l
f.s = a
f.x = b
f.z = b
l.s = b
l.w = b
l.v = j
l.z = f
l.x = i
assert l.v.x.x.o.z.z.txt == "b"