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

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

class C:
    def __init__(self, txt: str):
        self.t: D = None
        self.w: B = None
        self.y: B = None
        self.u: A = None
        self.o: B = None
        self.x: E = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.p: E = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.t: D = None
        self.w: B = None
        self.y: B = None
        self.u: A = None
        self.o: B = None
        self.x: E = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.p: E = None
        self.txt = txt

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

n.y = k
n.u = k
n.w = a
n.s = d
n.q = d
k.o = m
k.s = n
k.q = d
k.t = d
k.z = j
k.y = e
m.t = j
m.w = k
m.y = a
m.o = a
m.u = n
m.x = l
e.s = k
e.w = j
e.o = j
e.u = l
l.y = n
l.v = k
c.p = l
d.s = k
d.w = j
d.u = l
d.o = e
a.o = m
a.s = n
a.q = e
a.t = e
a.y = e
a.z = d
j.s = a
j.w = d
j.o = d
j.u = l
assert a.z.u.v.o.w.z.txt == "j"