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

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

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

class D:
    def __init__(self, txt: str):
        self.z: B = None
        self.t: I = None
        self.txt = txt

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

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

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

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

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.z: B = None
        self.t: I = None
        self.txt = txt

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

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

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

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

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

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

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