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

class B:
    def __init__(self, txt: str):
        self.s: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: G = None
        self.v: B = None
        self.u: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: E = None
        self.q: B = None
        self.x: A = None
        self.t: H = None
        self.z: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.t: D = None
        self.u: D = None
        self.r: D = None
        self.x: C = None
        self.s: C = None
        self.p: D = None
        self.z: I = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.s: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.z: G = None
        self.v: B = None
        self.u: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.p: E = None
        self.q: B = None
        self.x: A = None
        self.t: H = None
        self.z: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.t: D = None
        self.u: D = None
        self.r: D = None
        self.x: C = None
        self.s: C = None
        self.p: D = None
        self.z: I = None
        self.txt = txt

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

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

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