class A:
    def __init__(self, txt: str):
        self.v: D = None
        self.o: E = None
        self.t: E = None
        self.z: B = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.p: A = None
        self.s: B = None
        self.r: E = None
        self.o: B = None
        self.w: I = None
        self.txt = txt

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

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

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

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

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.p: A = None
        self.s: B = None
        self.r: E = None
        self.o: B = None
        self.w: I = None
        self.txt = txt

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

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

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

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

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

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

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