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

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

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

class D:
    def __init__(self, txt: str):
        self.w: F = None
        self.o: D = None
        self.t: A = None
        self.z: F = None
        self.y: F = None
        self.r: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.x: B = None
        self.v: E = None
        self.y: A = None
        self.w: D = None
        self.o: E = None
        self.r: A = None
        self.txt = txt

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

d.w = h
d.z = h
d.v = l
m.q = n
m.v = h
m.u = k
m.x = e
m.w = e
m.t = e
e.x = n
k.w = l
k.y = l
k.o = n
k.t = d
k.z = j
k.r = m
a.y = j
a.t = d
a.u = d
a.x = k
j.x = m
j.v = h
j.o = h
j.y = d
j.r = d
j.w = k
h.y = j
h.t = d
h.u = d
h.x = n
n.w = j
n.y = j
n.o = k
n.t = d
n.z = l
n.r = m
l.x = m
l.v = h
l.y = d
l.r = d
l.w = k
l.o = a
assert d.v.w.r.v.x.t.w.t.txt == "
class A:
    def __init__(self, txt: str):
        self.w: E = None
        self.v: F = None
        self.z: E = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.w: F = None
        self.o: D = None
        self.t: A = None
        self.z: F = None
        self.y: F = None
        self.r: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.x: B = None
        self.v: E = None
        self.y: A = None
        self.w: D = None
        self.o: E = None
        self.r: A = None
        self.txt = txt

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

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