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

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

class C:
    def __init__(self, txt: str):
        self.u: D = None
        self.x: H = None
        self.z: G = None
        self.q: F = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.u: I = None
        self.o: H = None
        self.p: I = None
        self.v: I = None
        self.w: B = None
        self.q: D = None
        self.x: C = None
        self.y: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: F = None
        self.x: I = None
        self.v: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.o: G = None
        self.p: E = None
        self.w: B = None
        self.t: H = None
        self.x: A = None
        self.z: F = None
        self.y: H = None
        self.q: D = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.v: H = None
        self.txt = txt

f = A("f")
h = B("h")
n = C("n")
i = D("i")
k = E("k")
b = F("b")
m = G("m")
j = H("j")
d = I("d")
l = J("l")

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

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

class C:
    def __init__(self, txt: str):
        self.u: D = None
        self.x: H = None
        self.z: G = None
        self.q: F = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.u: I = None
        self.o: H = None
        self.p: I = None
        self.v: I = None
        self.w: B = None
        self.q: D = None
        self.x: C = None
        self.y: H = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: F = None
        self.x: I = None
        self.v: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.o: G = None
        self.p: E = None
        self.w: B = None
        self.t: H = None
        self.x: A = None
        self.z: F = None
        self.y: H = None
        self.q: D = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.v: H = None
        self.txt = txt

f = A("f")
h = B("h")
n = C("n")
i = D("i")
k = E("k")
b = F("b")
m = G("m")
j = H("j")
d = I("d")
l = J("l")

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