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

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

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

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

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

i = A("i")
a = B("a")
b = C("b")
h = D("h")
k = E("k")
n = E("n")
c = B("c")
m = A("m")

i.v = n
i.t = b
i.y = b
i.o = m
i.u = k
a.o = i
a.t = k
a.p = k
a.z = h
a.r = n
b.u = h
b.t = h
b.v = c
h.o = b
h.t = a
h.r = k
h.p = n
k.t = b
k.w = b
n.t = b
n.w = b
c.o = i
c.t = k
c.p = n
c.r = n
c.z = h
m.v = n
m.t = b
m.y = b
m.o = i
m.u = k
assert k.t.t.r.t.u.p.t.t.txt == "
class A:
    def __init__(self, txt: str):
        self.v: E = None
        self.t: C = None
        self.o: A = None
        self.u: E = None
        self.y: C = None
        self.txt = txt

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

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

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

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

i = A("i")
a = B("a")
b = C("b")
h = D("h")
k = E("k")
n = E("n")
c = B("c")
m = A("m")

i.v = n
i.t = b
i.y = b
i.o = m
i.u = k
a.o = i
a.t = k
a.p = k
a.z = h
a.r = n
b.u = h
b.t = h
b.v = c
h.o = b
h.t = a
h.r = k
h.p = n
k.t = b
k.w = b
n.t = b
n.w = b
c.o = i
c.t = k
c.p = n
c.r = n
c.z = h
m.v = n
m.t = b
m.y = b
m.o = i
m.u = k
assert k.t.t.r.t.u.p.t.t.txt == "h"