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

class B:
    def __init__(self, txt: str):
        self.u: D = None
        self.v: I = None
        self.x: I = None
        self.p: I = None
        self.z: A = None
        self.o: H = None
        self.w: G = None
        self.s: I = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.w: C = None
        self.q: A = None
        self.r: C = None
        self.u: C = None
        self.t: F = None
        self.z: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: A = None
        self.v: C = None
        self.r: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: E = None
        self.p: D = None
        self.v: B = None
        self.q: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: F = None
        self.p: B = None
        self.y: E = None
        self.o: I = None
        self.z: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: I = None
        self.x: I = None
        self.y: G = None
        self.o: A = None
        self.w: I = None
        self.q: E = None
        self.p: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: D = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.u: D = None
        self.v: I = None
        self.x: I = None
        self.p: I = None
        self.z: A = None
        self.o: H = None
        self.w: G = None
        self.s: I = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.w: C = None
        self.q: A = None
        self.r: C = None
        self.u: C = None
        self.t: F = None
        self.z: B = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: A = None
        self.v: C = None
        self.r: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: E = None
        self.p: D = None
        self.v: B = None
        self.q: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: F = None
        self.p: B = None
        self.y: E = None
        self.o: I = None
        self.z: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: I = None
        self.x: I = None
        self.y: G = None
        self.o: A = None
        self.w: I = None
        self.q: E = None
        self.p: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: D = None
        self.txt = txt

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

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