class A:
    def __init__(self, txt: str):
        self.s: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.p: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: G = None
        self.x: H = None
        self.q: E = None
        self.p: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: B = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.z: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: A = None
        self.u: G = None
        self.r: G = None
        self.y: D = None
        self.x: C = None
        self.p: F = None
        self.s: G = None
        self.t: C = None
        self.v: F = None
        self.txt = txt

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

f = A("f")
n = B("n")
h = C("h")
a = D("a")
c = E("c")
e = F("e")
g = G("g")
l = H("l")
k = I("k")
i = E("i")

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

class B:
    def __init__(self, txt: str):
        self.p: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: G = None
        self.x: H = None
        self.q: E = None
        self.p: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.t: B = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.z: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.q: A = None
        self.u: G = None
        self.r: G = None
        self.y: D = None
        self.x: C = None
        self.p: F = None
        self.s: G = None
        self.t: C = None
        self.v: F = None
        self.txt = txt

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

f = A("f")
n = B("n")
h = C("h")
a = D("a")
c = E("c")
e = F("e")
g = G("g")
l = H("l")
k = I("k")
i = E("i")

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