class A:
    def __init__(self, txt: str):
        self.s: D = None
        self.v: G = None
        self.q: G = None
        self.r: D = None
        self.y: I = None
        self.u: B = None
        self.t: B = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.o: A = None
        self.x: H = None
        self.t: I = None
        self.r: G = None
        self.p: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.p: C = None
        self.s: B = None
        self.q: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: B = None
        self.o: A = None
        self.q: J = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.t: E = None
        self.z: E = None
        self.v: E = None
        self.y: B = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.o: A = None
        self.x: H = None
        self.t: I = None
        self.r: G = None
        self.p: F = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.p: C = None
        self.s: B = None
        self.q: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.u: B = None
        self.o: A = None
        self.q: J = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.t: E = None
        self.z: E = None
        self.v: E = None
        self.y: B = None
        self.txt = txt

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

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