class A:
    def __init__(self, txt: str):
        self.w: C = None
        self.z: E = None
        self.o: E = None
        self.txt = txt

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

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

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

class E:
    def __init__(self, txt: str):
        self.t: H = None
        self.u: B = None
        self.w: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.q: E = None
        self.z: B = None
        self.t: D = None
        self.o: B = None
        self.s: G = None
        self.txt = txt

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

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

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.t: H = None
        self.u: B = None
        self.w: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.q: E = None
        self.z: B = None
        self.t: D = None
        self.o: B = None
        self.s: G = None
        self.txt = txt

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

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

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