class A:
    def __init__(self, txt: str):
        self.o: B = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.t: E = None
        self.x: H = None
        self.p: C = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.r: A = None
        self.s: H = None
        self.u: D = None
        self.x: I = None
        self.p: E = None
        self.y: E = None
        self.t: D = None
        self.o: B = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.x: H = None
        self.v: A = None
        self.q: E = None
        self.z: D = None
        self.p: G = None
        self.w: E = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.t: E = None
        self.x: H = None
        self.p: C = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.r: A = None
        self.s: H = None
        self.u: D = None
        self.x: I = None
        self.p: E = None
        self.y: E = None
        self.t: D = None
        self.o: B = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.x: H = None
        self.v: A = None
        self.q: E = None
        self.z: D = None
        self.p: G = None
        self.w: E = None
        self.txt = txt

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

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