class A:
    def __init__(self, txt: str):
        self.y: G = None
        self.u: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: H = None
        self.v: F = None
        self.s: E = None
        self.p: F = None
        self.t: D = None
        self.x: G = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.w: F = None
        self.q: C = None
        self.r: B = None
        self.u: G = None
        self.s: H = None
        self.z: G = None
        self.x: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: E = None
        self.x: A = None
        self.p: E = None
        self.o: E = None
        self.s: F = None
        self.q: E = None
        self.r: H = None
        self.t: B = None
        self.u: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: I = None
        self.o: I = None
        self.p: C = None
        self.q: C = None
        self.u: D = None
        self.txt = txt

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

h = A("h")
d = B("d")
b = C("b")
e = D("e")
a = E("a")
l = F("l")
i = G("i")
c = H("c")
k = I("k")
j = C("j")

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

class B:
    def __init__(self, txt: str):
        self.y: H = None
        self.v: F = None
        self.s: E = None
        self.p: F = None
        self.t: D = None
        self.x: G = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.w: F = None
        self.q: C = None
        self.r: B = None
        self.u: G = None
        self.s: H = None
        self.z: G = None
        self.x: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: E = None
        self.x: A = None
        self.p: E = None
        self.o: E = None
        self.s: F = None
        self.q: E = None
        self.r: H = None
        self.t: B = None
        self.u: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: I = None
        self.o: I = None
        self.p: C = None
        self.q: C = None
        self.u: D = None
        self.txt = txt

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

h = A("h")
d = B("d")
b = C("b")
e = D("e")
a = E("a")
l = F("l")
i = G("i")
c = H("c")
k = I("k")
j = C("j")

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