class A:
    def __init__(self, txt: str):
        self.y: I = None
        self.v: G = None
        self.u: C = None
        self.q: E = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.q: F = None
        self.z: H = None
        self.r: H = None
        self.y: F = None
        self.w: A = None
        self.p: A = None
        self.u: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: G = None
        self.y: E = None
        self.t: F = None
        self.w: I = None
        self.s: G = None
        self.u: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.o: C = None
        self.y: H = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.x: F = None
        self.s: H = None
        self.v: B = None
        self.o: F = None
        self.w: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: E = None
        self.r: G = None
        self.y: G = None
        self.w: B = None
        self.u: B = None
        self.x: F = None
        self.s: E = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.q: F = None
        self.z: H = None
        self.r: H = None
        self.y: F = None
        self.w: A = None
        self.p: A = None
        self.u: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: G = None
        self.y: E = None
        self.t: F = None
        self.w: I = None
        self.s: G = None
        self.u: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.o: C = None
        self.y: H = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.x: F = None
        self.s: H = None
        self.v: B = None
        self.o: F = None
        self.w: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: E = None
        self.r: G = None
        self.y: G = None
        self.w: B = None
        self.u: B = None
        self.x: F = None
        self.s: E = None
        self.txt = txt

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

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

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