class A:
    def __init__(self, txt: str):
        self.o: J = None
        self.z: E = None
        self.r: I = None
        self.w: F = None
        self.p: B = None
        self.u: H = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: F = None
        self.r: H = None
        self.s: C = None
        self.v: E = None
        self.p: H = None
        self.y: H = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.r: C = None
        self.q: H = None
        self.z: A = None
        self.w: B = None
        self.y: A = None
        self.v: G = None
        self.p: A = None
        self.o: B = None
        self.u: H = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: A = None
        self.p: B = None
        self.r: B = None
        self.x: I = None
        self.v: E = None
        self.s: I = None
        self.u: H = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.r: B = None
        self.v: E = None
        self.o: A = None
        self.u: E = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.r: C = None
        self.t: A = None
        self.p: E = None
        self.x: C = None
        self.s: G = None
        self.u: E = None
        self.w: D = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.t: A = None
        self.q: H = None
        self.txt = txt

i = A("i")
n = B("n")
e = C("e")
f = D("f")
c = E("c")
h = F("h")
l = G("l")
a = H("a")
g = I("g")
b = J("b")

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

class B:
    def __init__(self, txt: str):
        self.u: F = None
        self.r: H = None
        self.s: C = None
        self.v: E = None
        self.p: H = None
        self.y: H = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.r: C = None
        self.q: H = None
        self.z: A = None
        self.w: B = None
        self.y: A = None
        self.v: G = None
        self.p: A = None
        self.o: B = None
        self.u: H = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: A = None
        self.p: B = None
        self.r: B = None
        self.x: I = None
        self.v: E = None
        self.s: I = None
        self.u: H = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.r: B = None
        self.v: E = None
        self.o: A = None
        self.u: E = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.r: C = None
        self.t: A = None
        self.p: E = None
        self.x: C = None
        self.s: G = None
        self.u: E = None
        self.w: D = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.t: A = None
        self.q: H = None
        self.txt = txt

i = A("i")
n = B("n")
e = C("e")
f = D("f")
c = E("c")
h = F("h")
l = G("l")
a = H("a")
g = I("g")
b = J("b")

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