class A:
    def __init__(self, txt: str):
        self.z: E = None
        self.q: I = None
        self.t: D = None
        self.y: H = None
        self.v: B = None
        self.u: E = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.v: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.x: H = None
        self.q: A = None
        self.z: A = None
        self.u: H = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.q: F = None
        self.v: G = None
        self.z: F = None
        self.r: C = None
        self.u: D = None
        self.w: I = None
        self.txt = txt

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.v: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.x: H = None
        self.q: A = None
        self.z: A = None
        self.u: H = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.q: F = None
        self.v: G = None
        self.z: F = None
        self.r: C = None
        self.u: D = None
        self.w: I = None
        self.txt = txt

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

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

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