class A:
    def __init__(self, txt: str):
        self.p: E = None
        self.v: E = None
        self.t: A = None
        self.txt = txt

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

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

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

class E:
    def __init__(self, txt: str):
        self.z: C = None
        self.s: A = None
        self.v: C = None
        self.t: C = None
        self.p: C = None
        self.txt = txt

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

a.p = c
a.v = c
a.t = f
e.s = g
i.z = e
i.o = e
i.r = j
i.t = l
h.v = c
h.o = c
h.p = e
h.s = i
c.z = i
c.t = i
c.p = i
c.s = a
c.v = j
f.p = c
f.v = c
f.t = a
l.v = c
l.o = c
l.p = e
l.s = j
g.v = c
g.o = c
g.p = e
g.s = i
b.p = c
b.v = c
b.t = f
j.z = e
j.o = e
j.r = i
j.t = h
assert e.s.o.s.t.t.t.p.v.r.txt == "
class A:
    def __init__(self, txt: str):
        self.p: E = None
        self.v: E = None
        self.t: A = None
        self.txt = txt

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

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

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

class E:
    def __init__(self, txt: str):
        self.z: C = None
        self.s: A = None
        self.v: C = None
        self.t: C = None
        self.p: C = None
        self.txt = txt

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

a.p = c
a.v = c
a.t = f
e.s = g
i.z = e
i.o = e
i.r = j
i.t = l
h.v = c
h.o = c
h.p = e
h.s = i
c.z = i
c.t = i
c.p = i
c.s = a
c.v = j
f.p = c
f.v = c
f.t = a
l.v = c
l.o = c
l.p = e
l.s = j
g.v = c
g.o = c
g.p = e
g.s = i
b.p = c
b.v = c
b.t = f
j.z = e
j.o = e
j.r = i
j.t = h
assert e.s.o.s.t.t.t.p.v.r.txt == "i"