class A:
    def __init__(self, txt: str):
        self.w: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.w: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.y: G = None
        self.u: I = None
        self.q: E = None
        self.s: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: G = None
        self.o: E = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.v: A = None
        self.u: E = None
        self.t: H = None
        self.z: E = None
        self.q: I = None
        self.s: G = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.v: G = None
        self.q: A = None
        self.t: E = None
        self.y: D = None
        self.r: F = None
        self.w: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.t: E = None
        self.y: B = None
        self.o: G = None
        self.x: D = None
        self.w: H = None
        self.z: C = None
        self.s: D = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.w: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.y: G = None
        self.u: I = None
        self.q: E = None
        self.s: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: G = None
        self.o: E = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.v: A = None
        self.u: E = None
        self.t: H = None
        self.z: E = None
        self.q: I = None
        self.s: G = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.v: G = None
        self.q: A = None
        self.t: E = None
        self.y: D = None
        self.r: F = None
        self.w: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.t: E = None
        self.y: B = None
        self.o: G = None
        self.x: D = None
        self.w: H = None
        self.z: C = None
        self.s: D = None
        self.txt = txt

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

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