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

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

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

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

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

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

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

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

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

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

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

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

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

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

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