class A:
    def __init__(self, txt: str):
        self.z: E = None
        self.y: G = None
        self.w: I = None
        self.s: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.t: C = None
        self.u: G = None
        self.r: E = None
        self.q: J = None
        self.y: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: H = None
        self.r: B = None
        self.t: J = None
        self.s: A = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.t: A = None
        self.p: J = None
        self.z: D = None
        self.o: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: J = None
        self.z: G = None
        self.s: C = None
        self.u: G = None
        self.q: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.u: B = None
        self.t: D = None
        self.r: B = None
        self.v: A = None
        self.z: J = None
        self.q: C = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.t: C = None
        self.u: G = None
        self.r: E = None
        self.q: J = None
        self.y: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: H = None
        self.r: B = None
        self.t: J = None
        self.s: A = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.t: A = None
        self.p: J = None
        self.z: D = None
        self.o: D = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: J = None
        self.z: G = None
        self.s: C = None
        self.u: G = None
        self.q: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.u: B = None
        self.t: D = None
        self.r: B = None
        self.v: A = None
        self.z: J = None
        self.q: C = None
        self.txt = txt

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

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

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