class A:
    def __init__(self, txt: str):
        self.x: E = None
        self.s: B = None
        self.p: E = None
        self.y: A = None
        self.t: A = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.x: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: B = None
        self.o: C = None
        self.z: A = None
        self.txt = txt

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

c = A("c")
e = B("e")
d = C("d")
b = D("b")
h = E("h")
k = E("k")
l = A("l")

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

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

class C:
    def __init__(self, txt: str):
        self.x: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: B = None
        self.o: C = None
        self.z: A = None
        self.txt = txt

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

c = A("c")
e = B("e")
d = C("d")
b = D("b")
h = E("h")
k = E("k")
l = A("l")

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