class A:
    def __init__(self, txt: str):
        self.o: E = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.t: J = None
        self.p: I = None
        self.r: A = None
        self.u: I = None
        self.q: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: I = None
        self.v: B = None
        self.s: E = None
        self.o: J = None
        self.q: G = None
        self.p: J = None
        self.t: F = None
        self.r: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.u: A = None
        self.x: B = None
        self.v: C = None
        self.r: E = None
        self.s: J = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: C = None
        self.q: E = None
        self.s: C = None
        self.z: B = None
        self.u: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: I = None
        self.x: C = None
        self.z: F = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.r: C = None
        self.o: F = None
        self.x: F = None
        self.u: H = None
        self.s: B = None
        self.q: C = None
        self.p: B = None
        self.t: E = None
        self.y: F = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.t: J = None
        self.p: I = None
        self.r: A = None
        self.u: I = None
        self.q: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: I = None
        self.v: B = None
        self.s: E = None
        self.o: J = None
        self.q: G = None
        self.p: J = None
        self.t: F = None
        self.r: G = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.u: A = None
        self.x: B = None
        self.v: C = None
        self.r: E = None
        self.s: J = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: C = None
        self.q: E = None
        self.s: C = None
        self.z: B = None
        self.u: I = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: I = None
        self.x: C = None
        self.z: F = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.r: C = None
        self.o: F = None
        self.x: F = None
        self.u: H = None
        self.s: B = None
        self.q: C = None
        self.p: B = None
        self.t: E = None
        self.y: F = None
        self.txt = txt

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

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