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

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

class C:
    def __init__(self, txt: str):
        self.w: F = None
        self.p: H = None
        self.x: E = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.y: G = None
        self.w: B = None
        self.z: B = None
        self.q: H = None
        self.u: B = None
        self.x: I = None
        self.t: E = None
        self.v: I = None
        self.o: I = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.y: B = None
        self.r: C = None
        self.p: C = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.w: F = None
        self.p: H = None
        self.x: E = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.y: G = None
        self.w: B = None
        self.z: B = None
        self.q: H = None
        self.u: B = None
        self.x: I = None
        self.t: E = None
        self.v: I = None
        self.o: I = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.y: B = None
        self.r: C = None
        self.p: C = None
        self.txt = txt

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

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

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