class A:
    def __init__(self, txt: str):
        self.z: I = None
        self.u: I = None
        self.p: G = None
        self.y: C = None
        self.x: F = None
        self.o: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: E = None
        self.z: A = None
        self.q: F = None
        self.w: J = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.p: B = None
        self.w: I = None
        self.s: E = None
        self.r: I = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.q: I = None
        self.s: J = None
        self.u: A = None
        self.r: H = None
        self.w: I = None
        self.x: J = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.z: D = None
        self.o: C = None
        self.q: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.v: J = None
        self.p: H = None
        self.s: D = None
        self.y: A = None
        self.q: H = None
        self.u: B = None
        self.t: F = None
        self.w: A = None
        self.z: B = None
        self.o: G = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.v: G = None
        self.p: B = None
        self.z: D = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.s: E = None
        self.z: A = None
        self.q: F = None
        self.w: J = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.p: B = None
        self.w: I = None
        self.s: E = None
        self.r: I = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.q: I = None
        self.s: J = None
        self.u: A = None
        self.r: H = None
        self.w: I = None
        self.x: J = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.z: D = None
        self.o: C = None
        self.q: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.v: J = None
        self.p: H = None
        self.s: D = None
        self.y: A = None
        self.q: H = None
        self.u: B = None
        self.t: F = None
        self.w: A = None
        self.z: B = None
        self.o: G = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.v: G = None
        self.p: B = None
        self.z: D = None
        self.txt = txt

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

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