class A:
    def __init__(self, txt: str):
        self.x: J = None
        self.y: H = None
        self.o: F = None
        self.s: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: I = None
        self.u: D = None
        self.y: I = None
        self.x: F = None
        self.o: C = None
        self.q: J = None
        self.t: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.z: A = None
        self.s: G = None
        self.o: H = None
        self.u: G = None
        self.p: I = None
        self.y: A = None
        self.x: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: C = None
        self.u: F = None
        self.q: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: B = None
        self.q: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: J = None
        self.v: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: D = None
        self.w: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: C = None
        self.t: H = None
        self.q: J = None
        self.o: F = None
        self.txt = txt

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

a = A("a")
n = B("n")
h = C("h")
g = D("g")
f = E("f")
j = F("j")
k = G("k")
l = H("l")
d = I("d")
c = J("c")

a.x = c
a.y = l
a.o = j
a.s = n
n.v = d
n.y = d
n.u = g
n.t = g
n.x = j
n.o = h
n.q = c
h.y = j
h.t = c
h.o = c
h.r = n
h.q = n
h.s = k
h.z = d
h.x = f
g.z = a
g.y = a
g.s = k
g.u = k
g.x = k
g.o = l
g.p = d
f.t = h
f.u = j
f.q = n
j.x = n
j.q = a
k.s = c
k.v = l
l.y = g
l.w = a
d.s = h
d.t = l
d.q = c
d.o = j
c.s = h
c.v = h
c.t = a
c.o = g
c.x = l
c.p = n
c.u = n
assert a.s.v.o.q.y.y.u.s.t.x.txt == "
class A:
    def __init__(self, txt: str):
        self.x: J = None
        self.y: H = None
        self.o: F = None
        self.s: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: I = None
        self.u: D = None
        self.y: I = None
        self.x: F = None
        self.o: C = None
        self.q: J = None
        self.t: D = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.z: A = None
        self.s: G = None
        self.o: H = None
        self.u: G = None
        self.p: I = None
        self.y: A = None
        self.x: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.t: C = None
        self.u: F = None
        self.q: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: B = None
        self.q: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: J = None
        self.v: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.y: D = None
        self.w: A = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: C = None
        self.t: H = None
        self.q: J = None
        self.o: F = None
        self.txt = txt

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

a = A("a")
n = B("n")
h = C("h")
g = D("g")
f = E("f")
j = F("j")
k = G("k")
l = H("l")
d = I("d")
c = J("c")

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