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

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

class C:
    def __init__(self, txt: str):
        self.u: B = None
        self.o: A = None
        self.v: B = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.r: E = None
        self.z: A = None
        self.u: C = None
        self.s: E = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.u: B = None
        self.o: A = None
        self.v: B = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.r: E = None
        self.z: A = None
        self.u: C = None
        self.s: E = None
        self.txt = txt

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

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