class A:
    def __init__(self, txt: str):
        self.t: H = None
        self.y: G = None
        self.z: B = None
        self.w: B = None
        self.r: G = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: A = None
        self.x: A = None
        self.o: H = None
        self.y: H = None
        self.s: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: G = None
        self.t: G = None
        self.p: E = None
        self.v: E = None
        self.z: F = None
        self.w: E = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.w: H = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.t: C = None
        self.q: C = None
        self.p: I = None
        self.w: C = None
        self.v: H = None
        self.u: F = None
        self.o: D = None
        self.x: F = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.u: A = None
        self.v: F = None
        self.y: E = None
        self.q: H = None
        self.x: G = None
        self.r: B = None
        self.t: F = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.u: A = None
        self.x: A = None
        self.o: H = None
        self.y: H = None
        self.s: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.x: G = None
        self.t: G = None
        self.p: E = None
        self.v: E = None
        self.z: F = None
        self.w: E = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.w: H = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.t: C = None
        self.q: C = None
        self.p: I = None
        self.w: C = None
        self.v: H = None
        self.u: F = None
        self.o: D = None
        self.x: F = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.u: A = None
        self.v: F = None
        self.y: E = None
        self.q: H = None
        self.x: G = None
        self.r: B = None
        self.t: F = None
        self.txt = txt

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

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