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

class B:
    def __init__(self, txt: str):
        self.o: F = None
        self.p: E = None
        self.q: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.o: B = None
        self.z: H = None
        self.u: D = None
        self.p: G = None
        self.w: F = None
        self.y: F = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.t: H = None
        self.p: C = None
        self.s: G = None
        self.r: A = None
        self.txt = txt

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.o: F = None
        self.p: E = None
        self.q: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.o: B = None
        self.z: H = None
        self.u: D = None
        self.p: G = None
        self.w: F = None
        self.y: F = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.t: H = None
        self.p: C = None
        self.s: G = None
        self.r: A = None
        self.txt = txt

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

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

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

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

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