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

class B:
    def __init__(self, txt: str):
        self.x: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.p: H = None
        self.z: B = None
        self.w: B = None
        self.v: C = None
        self.s: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: I = None
        self.t: I = None
        self.o: I = None
        self.w: A = None
        self.p: H = None
        self.q: A = None
        self.y: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: B = None
        self.r: J = None
        self.w: A = None
        self.y: C = None
        self.x: C = None
        self.txt = txt

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

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

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

class J:
    def __init__(self, txt: str):
        self.y: I = None
        self.w: G = None
        self.t: E = None
        self.o: H = None
        self.q: H = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.x: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.p: H = None
        self.z: B = None
        self.w: B = None
        self.v: C = None
        self.s: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: I = None
        self.t: I = None
        self.o: I = None
        self.w: A = None
        self.p: H = None
        self.q: A = None
        self.y: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.p: B = None
        self.r: J = None
        self.w: A = None
        self.y: C = None
        self.x: C = None
        self.txt = txt

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

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

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

class J:
    def __init__(self, txt: str):
        self.y: I = None
        self.w: G = None
        self.t: E = None
        self.o: H = None
        self.q: H = None
        self.txt = txt

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

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