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

class B:
    def __init__(self, txt: str):
        self.r: D = None
        self.y: F = None
        self.t: C = None
        self.p: E = None
        self.o: C = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.v: D = None
        self.s: C = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.r: D = None
        self.y: F = None
        self.t: C = None
        self.p: E = None
        self.o: C = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.v: D = None
        self.s: C = None
        self.txt = txt

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

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

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