class A:
    def __init__(self, txt: str):
        self.p: C = None
        self.r: A = None
        self.z: C = None
        self.y: E = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.o: A = None
        self.w: E = None
        self.v: A = None
        self.y: A = None
        self.txt = txt

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.o: A = None
        self.w: E = None
        self.v: A = None
        self.y: A = None
        self.txt = txt

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

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

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