class A:
    def __init__(self, txt: str):
        self.y: B = None
        self.v: J = None
        self.o: G = None
        self.z: F = None
        self.u: G = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: D = None
        self.p: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: C = None
        self.v: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.w: H = None
        self.y: J = None
        self.x: C = None
        self.s: D = None
        self.t: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: J = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.r: A = None
        self.p: D = None
        self.q: H = None
        self.u: F = None
        self.w: C = None
        self.z: I = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.o: D = None
        self.p: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: C = None
        self.v: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.w: H = None
        self.y: J = None
        self.x: C = None
        self.s: D = None
        self.t: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: J = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.r: A = None
        self.p: D = None
        self.q: H = None
        self.u: F = None
        self.w: C = None
        self.z: I = None
        self.txt = txt

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

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