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

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

class C:
    def __init__(self, txt: str):
        self.t: H = None
        self.q: H = None
        self.p: D = None
        self.w: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: H = None
        self.o: C = None
        self.s: F = None
        self.u: F = None
        self.x: H = None
        self.r: E = None
        self.z: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: F = None
        self.v: A = None
        self.p: D = None
        self.o: G = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.w: E = None
        self.x: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.x: B = None
        self.y: G = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.t: H = None
        self.q: H = None
        self.p: D = None
        self.w: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: H = None
        self.o: C = None
        self.s: F = None
        self.u: F = None
        self.x: H = None
        self.r: E = None
        self.z: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: F = None
        self.v: A = None
        self.p: D = None
        self.o: G = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.w: E = None
        self.x: B = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.x: B = None
        self.y: G = None
        self.txt = txt

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

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

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