class A:
    def __init__(self, txt: str):
        self.x: I = None
        self.q: G = None
        self.r: J = None
        self.o: J = None
        self.u: G = None
        self.p: J = None
        self.s: F = None
        self.v: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: A = None
        self.s: E = None
        self.t: D = None
        self.v: J = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: E = None
        self.p: H = None
        self.w: B = None
        self.u: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: A = None
        self.s: H = None
        self.q: H = None
        self.x: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: D = None
        self.y: A = None
        self.q: A = None
        self.u: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.q: D = None
        self.r: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: J = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.u: A = None
        self.s: E = None
        self.t: D = None
        self.v: J = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: E = None
        self.p: H = None
        self.w: B = None
        self.u: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: A = None
        self.s: H = None
        self.q: H = None
        self.x: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: D = None
        self.y: A = None
        self.q: A = None
        self.u: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.q: D = None
        self.r: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: J = None
        self.txt = txt

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

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

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