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

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

class C:
    def __init__(self, txt: str):
        self.u: D = None
        self.s: D = None
        self.z: B = None
        self.q: E = None
        self.w: C = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: E = None
        self.z: A = None
        self.u: A = None
        self.txt = txt

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

e = A("e")
n = B("n")
i = C("i")
m = D("m")
l = E("l")
d = A("d")
c = C("c")
f = E("f")
k = A("k")

e.z = m
e.u = l
e.x = f
e.t = n
n.u = d
n.r = c
i.u = m
i.s = m
i.z = n
i.q = l
i.w = c
m.w = f
m.z = k
m.u = e
l.w = n
l.o = c
d.z = m
d.u = f
d.x = f
d.t = n
c.u = m
c.s = m
c.z = n
c.q = l
c.w = i
f.w = n
f.o = i
k.z = m
k.u = l
k.x = f
k.t = n
assert i.q.w.r.z.txt == "
class A:
    def __init__(self, txt: str):
        self.z: D = None
        self.u: E = None
        self.x: E = None
        self.t: B = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.u: D = None
        self.s: D = None
        self.z: B = None
        self.q: E = None
        self.w: C = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: E = None
        self.z: A = None
        self.u: A = None
        self.txt = txt

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

e = A("e")
n = B("n")
i = C("i")
m = D("m")
l = E("l")
d = A("d")
c = C("c")
f = E("f")
k = A("k")

e.z = m
e.u = l
e.x = f
e.t = n
n.u = d
n.r = c
i.u = m
i.s = m
i.z = n
i.q = l
i.w = c
m.w = f
m.z = k
m.u = e
l.w = n
l.o = c
d.z = m
d.u = f
d.x = f
d.t = n
c.u = m
c.s = m
c.z = n
c.q = l
c.w = i
f.w = n
f.o = i
k.z = m
k.u = l
k.x = f
k.t = n
assert i.q.w.r.z.txt == "n"