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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.w: D = None
        self.q: D = None
        self.t: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: E = None
        self.o: I = None
        self.v: A = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.y: F = None
        self.v: C = None
        self.w: C = None
        self.x: D = None
        self.p: F = None
        self.o: E = None
        self.txt = txt

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

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.w: D = None
        self.q: D = None
        self.t: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: E = None
        self.o: I = None
        self.v: A = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.y: F = None
        self.v: C = None
        self.w: C = None
        self.x: D = None
        self.p: F = None
        self.o: E = None
        self.txt = txt

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

b.u = k
b.w = f
g.o = f
g.t = l
f.x = d
f.z = n
f.t = a
f.w = b
f.v = l
n.x = a
n.t = a
n.o = b
n.s = d
n.y = d
n.z = k
n.p = f
n.v = l
a.y = g
a.t = l
d.w = n
d.q = n
d.t = f
k.s = a
k.o = l
k.v = b
h.y = n
h.t = f
h.z = g
l.y = d
l.p = d
l.v = f
l.w = f
l.x = n
l.o = a
assert b.w.v.o.t.w.t.txt == "a"