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

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

class C:
    def __init__(self, txt: str):
        self.s: C = None
        self.u: C = None
        self.t: C = None
        self.w: C = None
        self.p: D = None
        self.o: A = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.q: A = None
        self.x: E = None
        self.s: C = None
        self.u: B = None
        self.v: B = None
        self.w: A = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.s: C = None
        self.u: C = None
        self.t: C = None
        self.w: C = None
        self.p: D = None
        self.o: A = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.q: A = None
        self.x: E = None
        self.s: C = None
        self.u: B = None
        self.v: B = None
        self.w: A = None
        self.txt = txt

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

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