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

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

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

class D:
    def __init__(self, txt: str):
        self.p: E = None
        self.y: D = None
        self.o: C = None
        self.t: A = None
        self.txt = txt

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.p: E = None
        self.y: D = None
        self.o: C = None
        self.t: A = None
        self.txt = txt

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

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

e.w = f
e.x = c
e.t = a
e.s = m
l.z = i
l.x = a
l.u = a
l.o = k
l.t = k
a.u = f
a.q = l
i.p = c
i.y = m
i.o = a
i.t = h
c.r = a
c.t = e
c.w = l
c.q = m
c.v = k
m.p = c
m.y = f
m.o = a
m.t = h
f.p = c
f.y = m
f.o = a
f.t = h
h.w = f
h.s = f
h.x = c
h.t = a
k.z = m
k.x = a
k.u = a
k.o = l
k.t = l
assert c.v.z.p.t.s.p.r.u.txt == "f"