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

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

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

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

class E:
    def __init__(self, txt: str):
        self.x: D = None
        self.p: H = None
        self.t: D = None
        self.s: C = None
        self.y: H = None
        self.u: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: I = None
        self.txt = txt

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

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

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

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

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.x: D = None
        self.p: H = None
        self.t: D = None
        self.s: C = None
        self.y: H = None
        self.u: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: I = None
        self.txt = txt

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

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

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

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

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