class A:
    def __init__(self, txt: str):
        self.x: I = None
        self.p: F = None
        self.z: G = None
        self.s: G = None
        self.q: I = None
        self.t: B = None
        self.y: C = None
        self.w: F = None
        self.v: B = None
        self.r: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: I = None
        self.s: I = None
        self.o: D = None
        self.r: J = None
        self.v: E = None
        self.x: D = None
        self.t: F = None
        self.z: F = None
        self.p: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.o: J = None
        self.y: G = None
        self.x: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: C = None
        self.w: B = None
        self.y: C = None
        self.v: A = None
        self.r: C = None
        self.x: J = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.r: C = None
        self.u: B = None
        self.p: B = None
        self.o: D = None
        self.z: F = None
        self.s: H = None
        self.v: J = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: D = None
        self.x: I = None
        self.y: A = None
        self.u: E = None
        self.p: F = None
        self.w: D = None
        self.s: D = None
        self.txt = txt

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

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

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

n.x = m
n.q = m
n.p = k
n.w = k
n.r = k
n.z = j
n.s = j
n.t = e
n.v = e
n.y = b
e.q = b
b.y = m
b.s = m
b.o = f
b.x = f
b.r = d
b.v = a
b.t = k
b.z = k
b.p = j
f.o = d
f.y = j
f.x = l
a.p = b
a.y = b
a.r = b
a.w = e
a.v = n
a.x = d
k.s = d
k.u = d
k.r = b
k.z = b
k.y = b
k.t = f
k.o = f
k.w = a
k.x = l
j.r = b
j.u = e
j.p = e
j.o = f
j.z = k
j.s = l
j.v = d
l.q = f
l.w = f
l.s = f
l.x = m
l.y = n
l.u = a
l.p = k
m.o = l
m.t = f
d.q = f
d.r = n
d.v = j
d.o = a
assert n.z.r.x.x.u.txt == "
class A:
    def __init__(self, txt: str):
        self.x: I = None
        self.p: F = None
        self.z: G = None
        self.s: G = None
        self.q: I = None
        self.t: B = None
        self.y: C = None
        self.w: F = None
        self.v: B = None
        self.r: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: C = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: I = None
        self.s: I = None
        self.o: D = None
        self.r: J = None
        self.v: E = None
        self.x: D = None
        self.t: F = None
        self.z: F = None
        self.p: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.o: J = None
        self.y: G = None
        self.x: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: C = None
        self.w: B = None
        self.y: C = None
        self.v: A = None
        self.r: C = None
        self.x: J = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.r: C = None
        self.u: B = None
        self.p: B = None
        self.o: D = None
        self.z: F = None
        self.s: H = None
        self.v: J = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: D = None
        self.x: I = None
        self.y: A = None
        self.u: E = None
        self.p: F = None
        self.w: D = None
        self.s: D = None
        self.txt = txt

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

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

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

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