class A:
    def __init__(self, txt: str):
        self.y: G = None
        self.t: G = None
        self.o: F = None
        self.q: D = None
        self.txt = txt

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

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

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

class E:
    def __init__(self, txt: str):
        self.v: D = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.y: C = None
        self.t: J = None
        self.u: A = None
        self.r: I = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.o: G = None
        self.z: A = None
        self.u: F = None
        self.t: E = None
        self.s: B = None
        self.x: H = None
        self.q: D = None
        self.r: J = None
        self.txt = txt

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

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

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.v: D = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.y: C = None
        self.t: J = None
        self.u: A = None
        self.r: I = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.o: G = None
        self.z: A = None
        self.u: F = None
        self.t: E = None
        self.s: B = None
        self.x: H = None
        self.q: D = None
        self.r: J = None
        self.txt = txt

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

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

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