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

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

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

class D:
    def __init__(self, txt: str):
        self.p: F = None
        self.t: F = None
        self.v: A = None
        self.o: C = None
        self.x: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: B = None
        self.y: F = None
        self.z: F = None
        self.x: A = None
        self.q: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: E = None
        self.z: F = None
        self.w: A = None
        self.x: A = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.p: F = None
        self.t: F = None
        self.v: A = None
        self.o: C = None
        self.x: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: B = None
        self.y: F = None
        self.z: F = None
        self.x: A = None
        self.q: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: E = None
        self.z: F = None
        self.w: A = None
        self.x: A = None
        self.txt = txt

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

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