class A:
    def __init__(self, txt: str):
        self.z: B = None
        self.y: H = None
        self.r: D = None
        self.q: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: F = None
        self.w: D = None
        self.x: J = None
        self.z: J = None
        self.s: E = None
        self.y: C = None
        self.o: A = None
        self.v: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: G = None
        self.z: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: E = None
        self.r: C = None
        self.t: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: A = None
        self.v: F = None
        self.w: I = None
        self.y: A = None
        self.p: A = None
        self.t: H = None
        self.r: F = None
        self.q: H = None
        self.o: J = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.y: F = None
        self.txt = txt

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

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

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

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

k.z = f
k.y = a
k.r = n
k.q = b
f.u = l
f.w = n
f.x = c
f.z = c
f.s = g
f.y = b
f.v = b
f.o = k
b.s = i
b.z = e
n.s = g
n.t = g
n.r = b
g.x = k
g.y = k
g.p = k
g.v = l
g.r = l
g.w = e
g.t = a
g.q = a
g.o = c
l.o = n
l.p = g
i.y = l
a.s = k
a.t = e
e.o = k
e.t = g
e.w = b
e.u = a
c.w = e
assert k.z.s.x.txt == "
class A:
    def __init__(self, txt: str):
        self.z: B = None
        self.y: H = None
        self.r: D = None
        self.q: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: F = None
        self.w: D = None
        self.x: J = None
        self.z: J = None
        self.s: E = None
        self.y: C = None
        self.o: A = None
        self.v: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: G = None
        self.z: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: E = None
        self.r: C = None
        self.t: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: A = None
        self.v: F = None
        self.w: I = None
        self.y: A = None
        self.p: A = None
        self.t: H = None
        self.r: F = None
        self.q: H = None
        self.o: J = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.y: F = None
        self.txt = txt

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

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

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

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

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