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

class B:
    def __init__(self, txt: str):
        self.y: D = None
        self.u: B = None
        self.s: E = None
        self.txt = txt

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

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

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

e = A("e")
k = B("k")
c = C("c")
g = D("g")
i = E("i")
a = D("a")
j = B("j")
l = D("l")

e.v = i
e.q = c
e.w = c
k.y = a
k.u = j
k.s = i
c.r = k
c.q = g
c.z = e
c.y = i
g.y = k
i.x = e
i.w = j
i.t = c
i.q = g
a.y = j
j.y = l
j.u = k
j.s = i
l.y = j
assert k.s.t.y.q.y.u.u.txt == "
class A:
    def __init__(self, txt: str):
        self.v: E = None
        self.q: C = None
        self.w: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: D = None
        self.u: B = None
        self.s: E = None
        self.txt = txt

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

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

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

e = A("e")
k = B("k")
c = C("c")
g = D("g")
i = E("i")
a = D("a")
j = B("j")
l = D("l")

e.v = i
e.q = c
e.w = c
k.y = a
k.u = j
k.s = i
c.r = k
c.q = g
c.z = e
c.y = i
g.y = k
i.x = e
i.w = j
i.t = c
i.q = g
a.y = j
j.y = l
j.u = k
j.s = i
l.y = j
assert k.s.t.y.q.y.u.u.txt == "k"