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

class B:
    def __init__(self, txt: str):
        self.o: H = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: G = None
        self.u: I = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.o: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: C = None
        self.p: H = None
        self.q: E = None
        self.t: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: F = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.o: H = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.s: G = None
        self.u: I = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.o: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: C = None
        self.p: H = None
        self.q: E = None
        self.t: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.o: F = None
        self.txt = txt

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

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

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