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

class B:
    def __init__(self, txt: str):
        self.t: E = None
        self.r: A = None
        self.p: C = None
        self.z: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.t: I = None
        self.p: I = None
        self.q: I = None
        self.u: A = None
        self.o: C = None
        self.y: F = None
        self.w: I = None
        self.x: F = None
        self.s: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: G = None
        self.r: F = None
        self.x: G = None
        self.t: A = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.u: G = None
        self.t: F = None
        self.o: B = None
        self.w: G = None
        self.s: C = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.t: E = None
        self.r: A = None
        self.p: C = None
        self.z: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.t: I = None
        self.p: I = None
        self.q: I = None
        self.u: A = None
        self.o: C = None
        self.y: F = None
        self.w: I = None
        self.x: F = None
        self.s: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: G = None
        self.r: F = None
        self.x: G = None
        self.t: A = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.u: G = None
        self.t: F = None
        self.o: B = None
        self.w: G = None
        self.s: C = None
        self.txt = txt

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

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

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