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

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

class C:
    def __init__(self, txt: str):
        self.z: D = None
        self.v: G = None
        self.q: B = None
        self.y: H = None
        self.w: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: F = None
        self.x: J = None
        self.o: B = None
        self.p: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: H = None
        self.x: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: B = None
        self.q: H = None
        self.u: I = None
        self.v: G = None
        self.y: D = None
        self.s: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: B = None
        self.o: A = None
        self.u: C = None
        self.w: E = None
        self.p: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: I = None
        self.p: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.p: A = None
        self.v: E = None
        self.o: H = None
        self.r: D = None
        self.z: B = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.z: D = None
        self.v: G = None
        self.q: B = None
        self.y: H = None
        self.w: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: F = None
        self.x: J = None
        self.o: B = None
        self.p: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: H = None
        self.x: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: B = None
        self.q: H = None
        self.u: I = None
        self.v: G = None
        self.y: D = None
        self.s: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: B = None
        self.o: A = None
        self.u: C = None
        self.w: E = None
        self.p: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: I = None
        self.p: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.p: A = None
        self.v: E = None
        self.o: H = None
        self.r: D = None
        self.z: B = None
        self.txt = txt

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

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

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