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

class B:
    def __init__(self, txt: str):
        self.q: E = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.t: B = None
        self.r: E = None
        self.txt = txt

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

l = A("l")
g = B("g")
h = C("h")
f = D("f")
a = E("a")
b = D("b")
k = B("k")
d = B("d")
i = A("i")
m = C("m")

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

class B:
    def __init__(self, txt: str):
        self.q: E = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.t: B = None
        self.r: E = None
        self.txt = txt

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

l = A("l")
g = B("g")
h = C("h")
f = D("f")
a = E("a")
b = D("b")
k = B("k")
d = B("d")
i = A("i")
m = C("m")

l.z = a
l.y = a
l.x = i
l.s = g
g.q = a
h.p = k
h.z = m
h.v = m
h.q = a
f.t = g
f.r = a
a.u = g
a.r = g
a.o = f
a.p = k
a.q = h
b.t = k
b.r = a
k.q = a
d.q = a
i.z = a
i.y = a
i.x = l
i.s = g
m.p = g
m.z = h
m.v = h
m.q = a
assert d.q.o.t.q.o.txt == "f"