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

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

class C:
    def __init__(self, txt: str):
        self.w: F = None
        self.z: B = None
        self.p: I = None
        self.q: I = None
        self.v: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: C = None
        self.o: A = None
        self.u: A = None
        self.p: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: E = None
        self.v: A = None
        self.y: C = None
        self.p: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: A = None
        self.v: A = None
        self.w: B = None
        self.u: A = None
        self.t: D = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.p: B = None
        self.v: D = None
        self.t: G = None
        self.u: E = None
        self.q: C = None
        self.w: D = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.w: F = None
        self.z: B = None
        self.p: I = None
        self.q: I = None
        self.v: G = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: C = None
        self.o: A = None
        self.u: A = None
        self.p: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.q: E = None
        self.v: A = None
        self.y: C = None
        self.p: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: A = None
        self.v: A = None
        self.w: B = None
        self.u: A = None
        self.t: D = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.p: B = None
        self.v: D = None
        self.t: G = None
        self.u: E = None
        self.q: C = None
        self.w: D = None
        self.txt = txt

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

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