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

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

class C:
    def __init__(self, txt: str):
        self.v: J = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: H = None
        self.x: B = None
        self.q: I = None
        self.t: J = None
        self.w: H = None
        self.v: I = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.w: J = None
        self.t: D = None
        self.o: G = None
        self.v: G = None
        self.txt = txt

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

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

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

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.v: J = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: H = None
        self.x: B = None
        self.q: I = None
        self.t: J = None
        self.w: H = None
        self.v: I = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.w: J = None
        self.t: D = None
        self.o: G = None
        self.v: G = None
        self.txt = txt

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

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

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

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

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

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