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

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

class C:
    def __init__(self, txt: str):
        self.o: G = None
        self.x: J = None
        self.r: H = None
        self.u: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: A = None
        self.o: I = None
        self.y: J = None
        self.x: C = None
        self.z: C = None
        self.w: F = None
        self.t: F = None
        self.q: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: C = None
        self.v: D = None
        self.y: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: E = None
        self.y: A = None
        self.v: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.z: A = None
        self.w: A = None
        self.s: E = None
        self.txt = txt

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

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.o: G = None
        self.x: J = None
        self.r: H = None
        self.u: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: A = None
        self.o: I = None
        self.y: J = None
        self.x: C = None
        self.z: C = None
        self.w: F = None
        self.t: F = None
        self.q: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: C = None
        self.v: D = None
        self.y: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: E = None
        self.y: A = None
        self.v: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.z: A = None
        self.w: A = None
        self.s: E = None
        self.txt = txt

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

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

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

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