class A:
    def __init__(self, txt: str):
        self.v: E = None
        self.t: J = None
        self.o: C = None
        self.x: B = None
        self.r: D = None
        self.q: B = None
        self.u: F = None
        self.y: C = None
        self.s: E = None
        self.w: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: A = None
        self.v: C = None
        self.x: A = None
        self.o: H = None
        self.u: D = None
        self.q: A = None
        self.s: C = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: A = None
        self.y: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: F = None
        self.x: J = None
        self.r: A = None
        self.o: D = None
        self.v: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: B = None
        self.p: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: H = None
        self.z: A = None
        self.o: E = None
        self.v: B = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.u: G = None
        self.w: H = None
        self.p: G = None
        self.q: E = None
        self.y: E = None
        self.z: E = None
        self.s: D = None
        self.r: F = None
        self.o: H = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.z: A = None
        self.v: C = None
        self.x: A = None
        self.o: H = None
        self.u: D = None
        self.q: A = None
        self.s: C = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: A = None
        self.y: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: F = None
        self.x: J = None
        self.r: A = None
        self.o: D = None
        self.v: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: B = None
        self.p: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: H = None
        self.z: A = None
        self.o: E = None
        self.v: B = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.u: G = None
        self.w: H = None
        self.p: G = None
        self.q: E = None
        self.y: E = None
        self.z: E = None
        self.s: D = None
        self.r: F = None
        self.o: H = None
        self.txt = txt

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

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

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