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

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

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

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

class E:
    def __init__(self, txt: str):
        self.p: C = None
        self.v: D = None
        self.x: D = None
        self.r: A = None
        self.u: F = None
        self.y: F = None
        self.s: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: B = None
        self.r: C = None
        self.y: A = None
        self.q: I = None
        self.v: B = None
        self.p: B = None
        self.u: B = None
        self.x: G = None
        self.s: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: E = None
        self.p: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: C = None
        self.txt = txt

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

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

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.p: C = None
        self.v: D = None
        self.x: D = None
        self.r: A = None
        self.u: F = None
        self.y: F = None
        self.s: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: B = None
        self.r: C = None
        self.y: A = None
        self.q: I = None
        self.v: B = None
        self.p: B = None
        self.u: B = None
        self.x: G = None
        self.s: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: E = None
        self.p: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.z: C = None
        self.txt = txt

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

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

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