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

class B:
    def __init__(self, txt: str):
        self.v: F = None
        self.s: H = None
        self.o: J = None
        self.p: C = None
        self.z: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: E = None
        self.o: F = None
        self.r: B = None
        self.v: I = None
        self.y: B = None
        self.t: J = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.y: J = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.r: C = None
        self.x: J = None
        self.z: E = None
        self.w: A = None
        self.o: F = None
        self.q: J = None
        self.p: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: B = None
        self.w: E = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.v: E = None
        self.z: G = None
        self.x: A = None
        self.o: G = None
        self.y: I = None
        self.r: H = None
        self.w: F = None
        self.u: C = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.v: F = None
        self.s: H = None
        self.o: J = None
        self.p: C = None
        self.z: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: E = None
        self.o: F = None
        self.r: B = None
        self.v: I = None
        self.y: B = None
        self.t: J = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.y: J = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.r: C = None
        self.x: J = None
        self.z: E = None
        self.w: A = None
        self.o: F = None
        self.q: J = None
        self.p: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: B = None
        self.w: E = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.v: E = None
        self.z: G = None
        self.x: A = None
        self.o: G = None
        self.y: I = None
        self.r: H = None
        self.w: F = None
        self.u: C = None
        self.txt = txt

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

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