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

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

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

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

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

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

e = A("e")
m = B("m")
k = C("k")
n = D("n")
b = E("b")
i = F("i")
f = E("f")
l = B("l")
j = D("j")
c = F("c")

e.w = b
e.z = c
e.p = c
e.y = j
m.v = j
m.t = f
m.r = b
m.q = b
m.y = e
k.o = c
k.x = n
n.w = m
b.v = j
b.s = e
b.p = m
b.x = n
i.s = j
i.z = c
f.v = j
f.x = j
f.s = e
f.p = l
l.v = j
l.t = b
l.r = b
l.q = b
l.y = e
j.w = l
c.s = n
c.z = i
assert c.z.z.s.w.r.x.w.r.x.txt == "
class A:
    def __init__(self, txt: str):
        self.w: E = None
        self.z: F = None
        self.y: D = None
        self.p: F = None
        self.txt = txt

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

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

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

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

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

e = A("e")
m = B("m")
k = C("k")
n = D("n")
b = E("b")
i = F("i")
f = E("f")
l = B("l")
j = D("j")
c = F("c")

e.w = b
e.z = c
e.p = c
e.y = j
m.v = j
m.t = f
m.r = b
m.q = b
m.y = e
k.o = c
k.x = n
n.w = m
b.v = j
b.s = e
b.p = m
b.x = n
i.s = j
i.z = c
f.v = j
f.x = j
f.s = e
f.p = l
l.v = j
l.t = b
l.r = b
l.q = b
l.y = e
j.w = l
c.s = n
c.z = i
assert c.z.z.s.w.r.x.w.r.x.txt == "n"