class A:
    def __init__(self, txt: str):
        self.u: B = None
        self.p: F = None
        self.w: B = None
        self.x: B = None
        self.o: F = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.p: I = None
        self.t: B = None
        self.x: G = None
        self.s: H = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.q: C = None
        self.p: F = None
        self.z: B = None
        self.t: H = None
        self.o: I = None
        self.r: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: I = None
        self.v: I = None
        self.o: G = None
        self.t: I = None
        self.z: F = None
        self.s: G = None
        self.p: I = None
        self.q: F = None
        self.txt = txt

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

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.p: I = None
        self.t: B = None
        self.x: G = None
        self.s: H = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.q: C = None
        self.p: F = None
        self.z: B = None
        self.t: H = None
        self.o: I = None
        self.r: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: I = None
        self.v: I = None
        self.o: G = None
        self.t: I = None
        self.z: F = None
        self.s: G = None
        self.p: I = None
        self.q: F = None
        self.txt = txt

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

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

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

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