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

class B:
    def __init__(self, txt: str):
        self.o: C = None
        self.p: F = None
        self.q: E = None
        self.v: F = None
        self.z: D = None
        self.w: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: H = None
        self.t: E = None
        self.u: D = None
        self.q: F = None
        self.o: G = None
        self.p: D = None
        self.y: A = None
        self.z: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.q: B = None
        self.y: C = None
        self.z: E = None
        self.x: H = None
        self.v: E = None
        self.p: G = None
        self.t: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: A = None
        self.w: C = None
        self.r: C = None
        self.x: E = None
        self.q: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: B = None
        self.txt = txt

e = A("e")
a = B("a")
k = C("k")
i = D("i")
l = E("l")
b = F("b")
c = G("c")
h = H("h")
d = D("d")
f = E("f")

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

class B:
    def __init__(self, txt: str):
        self.o: C = None
        self.p: F = None
        self.q: E = None
        self.v: F = None
        self.z: D = None
        self.w: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: H = None
        self.t: E = None
        self.u: D = None
        self.q: F = None
        self.o: G = None
        self.p: D = None
        self.y: A = None
        self.z: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.q: B = None
        self.y: C = None
        self.z: E = None
        self.x: H = None
        self.v: E = None
        self.p: G = None
        self.t: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: A = None
        self.w: C = None
        self.r: C = None
        self.x: E = None
        self.q: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: B = None
        self.txt = txt

e = A("e")
a = B("a")
k = C("k")
i = D("i")
l = E("l")
b = F("b")
c = G("c")
h = H("h")
d = D("d")
f = E("f")

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