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

class B:
    def __init__(self, txt: str):
        self.z: G = None
        self.x: G = None
        self.w: C = None
        self.u: E = None
        self.r: E = None
        self.p: G = None
        self.y: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: E = None
        self.v: A = None
        self.o: H = None
        self.t: B = None
        self.q: B = None
        self.w: I = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.y: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: F = None
        self.s: B = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.p: I = None
        self.x: B = None
        self.u: G = None
        self.r: H = None
        self.q: C = None
        self.y: H = None
        self.z: C = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.z: G = None
        self.x: G = None
        self.w: C = None
        self.u: E = None
        self.r: E = None
        self.p: G = None
        self.y: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: E = None
        self.v: A = None
        self.o: H = None
        self.t: B = None
        self.q: B = None
        self.w: I = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.y: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: F = None
        self.s: B = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.p: I = None
        self.x: B = None
        self.u: G = None
        self.r: H = None
        self.q: C = None
        self.y: H = None
        self.z: C = None
        self.txt = txt

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

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