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

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

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

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

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

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

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

b.z = h
b.o = h
b.y = h
b.v = i
b.t = f
b.w = d
d.t = b
d.y = j
k.w = c
k.s = b
k.p = n
j.v = f
j.o = n
i.p = j
i.o = b
i.q = b
i.t = d
i.s = d
i.w = h
f.p = h
f.q = b
f.w = b
f.s = c
f.u = a
n.p = b
n.q = h
n.w = h
n.s = k
n.u = a
a.t = h
a.y = j
c.w = k
c.s = h
c.p = f
h.z = b
h.o = b
h.y = b
h.v = i
h.t = n
h.w = d
assert d.t.v.p.o.p.t.w.w.y.txt == "
class A:
    def __init__(self, txt: str):
        self.z: A = None
        self.v: E = None
        self.o: A = None
        self.y: A = None
        self.t: F = None
        self.w: B = None
        self.txt = txt

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

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

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

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

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

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

b.z = h
b.o = h
b.y = h
b.v = i
b.t = f
b.w = d
d.t = b
d.y = j
k.w = c
k.s = b
k.p = n
j.v = f
j.o = n
i.p = j
i.o = b
i.q = b
i.t = d
i.s = d
i.w = h
f.p = h
f.q = b
f.w = b
f.s = c
f.u = a
n.p = b
n.q = h
n.w = h
n.s = k
n.u = a
a.t = h
a.y = j
c.w = k
c.s = h
c.p = f
h.z = b
h.o = b
h.y = b
h.v = i
h.t = n
h.w = d
assert d.t.v.p.o.p.t.w.w.y.txt == "j"