class A:
    def __init__(self, txt: str):
        self.q: J = None
        self.r: E = None
        self.x: E = None
        self.o: J = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: G = None
        self.w: J = None
        self.z: G = None
        self.v: A = None
        self.r: H = None
        self.s: E = None
        self.u: H = None
        self.t: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: H = None
        self.y: J = None
        self.w: H = None
        self.x: J = None
        self.o: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: J = None
        self.p: H = None
        self.x: G = None
        self.y: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: J = None
        self.t: F = None
        self.z: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.y: H = None
        self.u: C = None
        self.p: H = None
        self.o: C = None
        self.s: G = None
        self.z: A = None
        self.w: F = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.x: G = None
        self.w: J = None
        self.z: G = None
        self.v: A = None
        self.r: H = None
        self.s: E = None
        self.u: H = None
        self.t: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: H = None
        self.y: J = None
        self.w: H = None
        self.x: J = None
        self.o: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: J = None
        self.p: H = None
        self.x: G = None
        self.y: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.q: J = None
        self.t: F = None
        self.z: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.y: H = None
        self.u: C = None
        self.p: H = None
        self.o: C = None
        self.s: G = None
        self.z: A = None
        self.w: F = None
        self.txt = txt

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

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

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