class A:
    def __init__(self, txt: str):
        self.x: F = None
        self.s: F = None
        self.q: H = None
        self.v: G = None
        self.o: F = None
        self.r: I = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.t: E = None
        self.q: A = None
        self.z: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: I = None
        self.t: C = None
        self.o: H = None
        self.u: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: D = None
        self.o: A = None
        self.r: G = None
        self.y: G = None
        self.txt = txt

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

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

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.t: E = None
        self.q: A = None
        self.z: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: I = None
        self.t: C = None
        self.o: H = None
        self.u: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: D = None
        self.o: A = None
        self.r: G = None
        self.y: G = None
        self.txt = txt

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

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

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

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

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