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

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

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

class D:
    def __init__(self, txt: str):
        self.t: E = None
        self.q: I = None
        self.x: F = None
        self.w: A = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.r: F = None
        self.z: E = None
        self.v: E = None
        self.y: A = None
        self.x: C = None
        self.u: I = None
        self.t: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: B = None
        self.w: F = None
        self.x: E = None
        self.t: F = None
        self.y: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: A = None
        self.u: A = None
        self.v: D = None
        self.q: C = None
        self.y: C = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.t: E = None
        self.q: I = None
        self.x: F = None
        self.w: A = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.r: F = None
        self.z: E = None
        self.v: E = None
        self.y: A = None
        self.x: C = None
        self.u: I = None
        self.t: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: B = None
        self.w: F = None
        self.x: E = None
        self.t: F = None
        self.y: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: A = None
        self.u: A = None
        self.v: D = None
        self.q: C = None
        self.y: C = None
        self.txt = txt

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

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