class A:
    def __init__(self, txt: str):
        self.v: E = None
        self.t: E = None
        self.z: I = None
        self.y: C = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.o: G = None
        self.v: A = None
        self.x: G = None
        self.p: G = None
        self.y: F = None
        self.s: F = None
        self.q: B = None
        self.w: F = None
        self.z: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.q: D = None
        self.u: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: A = None
        self.z: G = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.x: B = None
        self.s: D = None
        self.v: E = None
        self.r: D = None
        self.w: C = None
        self.y: C = None
        self.p: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.t: E = None
        self.s: C = None
        self.u: D = None
        self.z: D = None
        self.y: A = None
        self.w: H = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.o: G = None
        self.v: A = None
        self.x: G = None
        self.p: G = None
        self.y: F = None
        self.s: F = None
        self.q: B = None
        self.w: F = None
        self.z: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.q: D = None
        self.u: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: A = None
        self.z: G = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.x: B = None
        self.s: D = None
        self.v: E = None
        self.r: D = None
        self.w: C = None
        self.y: C = None
        self.p: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.t: E = None
        self.s: C = None
        self.u: D = None
        self.z: D = None
        self.y: A = None
        self.w: H = None
        self.txt = txt

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

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