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

class B:
    def __init__(self, txt: str):
        self.z: G = None
        self.u: J = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: D = None
        self.p: I = None
        self.r: J = None
        self.w: H = None
        self.t: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: A = None
        self.o: B = None
        self.t: I = None
        self.v: J = None
        self.w: A = None
        self.z: A = None
        self.q: J = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.z: A = None
        self.s: D = None
        self.y: I = None
        self.t: A = None
        self.q: I = None
        self.w: C = None
        self.v: H = None
        self.p: J = None
        self.u: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: D = None
        self.u: H = None
        self.r: I = None
        self.w: C = None
        self.txt = txt

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.z: G = None
        self.u: J = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: D = None
        self.p: I = None
        self.r: J = None
        self.w: H = None
        self.t: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: A = None
        self.o: B = None
        self.t: I = None
        self.v: J = None
        self.w: A = None
        self.z: A = None
        self.q: J = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.z: A = None
        self.s: D = None
        self.y: I = None
        self.t: A = None
        self.q: I = None
        self.w: C = None
        self.v: H = None
        self.p: J = None
        self.u: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: D = None
        self.u: H = None
        self.r: I = None
        self.w: C = None
        self.txt = txt

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

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

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

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

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