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

class B:
    def __init__(self, txt: str):
        self.z: D = None
        self.q: G = None
        self.y: E = None
        self.s: D = None
        self.v: I = None
        self.u: I = None
        self.w: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: D = None
        self.s: E = None
        self.t: A = None
        self.q: A = None
        self.z: A = None
        self.o: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: H = None
        self.y: C = None
        self.w: H = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.u: D = None
        self.t: C = None
        self.o: B = None
        self.p: G = None
        self.w: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: E = None
        self.w: I = None
        self.t: I = None
        self.s: B = None
        self.q: D = None
        self.x: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: F = None
        self.o: F = None
        self.r: B = None
        self.p: B = None
        self.t: D = None
        self.w: D = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.z: D = None
        self.q: G = None
        self.y: E = None
        self.s: D = None
        self.v: I = None
        self.u: I = None
        self.w: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: D = None
        self.s: E = None
        self.t: A = None
        self.q: A = None
        self.z: A = None
        self.o: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: H = None
        self.y: C = None
        self.w: H = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.u: D = None
        self.t: C = None
        self.o: B = None
        self.p: G = None
        self.w: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: E = None
        self.w: I = None
        self.t: I = None
        self.s: B = None
        self.q: D = None
        self.x: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: F = None
        self.o: F = None
        self.r: B = None
        self.p: B = None
        self.t: D = None
        self.w: D = None
        self.txt = txt

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

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

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