class A:
    def __init__(self, txt: str):
        self.r: H = None
        self.t: G = None
        self.v: D = None
        self.p: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: D = None
        self.s: I = None
        self.u: B = None
        self.z: G = None
        self.t: I = None
        self.x: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.o: C = None
        self.t: H = None
        self.r: A = None
        self.v: B = None
        self.x: I = None
        self.y: A = None
        self.q: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: E = None
        self.o: B = None
        self.y: A = None
        self.q: D = None
        self.s: E = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.p: D = None
        self.x: E = None
        self.o: H = None
        self.y: G = None
        self.q: A = None
        self.r: A = None
        self.t: H = None
        self.u: G = None
        self.v: G = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.y: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: D = None
        self.s: I = None
        self.u: B = None
        self.z: G = None
        self.t: I = None
        self.x: I = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.o: C = None
        self.t: H = None
        self.r: A = None
        self.v: B = None
        self.x: I = None
        self.y: A = None
        self.q: I = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: E = None
        self.o: B = None
        self.y: A = None
        self.q: D = None
        self.s: E = None
        self.txt = txt

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

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

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

class I:
    def __init__(self, txt: str):
        self.p: D = None
        self.x: E = None
        self.o: H = None
        self.y: G = None
        self.q: A = None
        self.r: A = None
        self.t: H = None
        self.u: G = None
        self.v: G = None
        self.txt = txt

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

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