class A:
    def __init__(self, txt: str):
        self.z: C = None
        self.u: D = None
        self.y: C = None
        self.w: J = None
        self.s: J = None
        self.o: H = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.w: G = None
        self.q: D = None
        self.v: E = None
        self.u: J = None
        self.o: H = None
        self.y: J = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.t: I = None
        self.y: I = None
        self.v: H = None
        self.u: D = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.w: J = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.q: H = None
        self.s: A = None
        self.t: H = None
        self.txt = txt

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

n.z = k
n.y = k
n.u = b
n.w = a
n.s = a
n.o = d
i.w = c
i.q = b
i.v = m
i.u = a
i.y = a
i.o = d
k.q = n
k.p = d
k.t = l
k.x = b
k.y = a
k.w = a
b.x = j
m.x = j
m.u = j
m.r = j
m.t = j
m.v = l
m.p = k
m.z = k
m.o = a
m.y = c
j.t = l
j.y = l
j.v = d
j.u = b
c.o = l
c.v = n
c.y = n
c.r = m
c.t = m
c.p = b
c.x = b
d.r = j
d.o = l
d.u = n
d.s = a
d.q = i
d.t = c
l.w = a
a.q = d
a.t = d
a.s = n
assert n.s.s.o.s.s.o.o.w.s.u.txt == "
class A:
    def __init__(self, txt: str):
        self.z: C = None
        self.u: D = None
        self.y: C = None
        self.w: J = None
        self.s: J = None
        self.o: H = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.w: G = None
        self.q: D = None
        self.v: E = None
        self.u: J = None
        self.o: H = None
        self.y: J = None
        self.txt = txt

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

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

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

class F:
    def __init__(self, txt: str):
        self.t: I = None
        self.y: I = None
        self.v: H = None
        self.u: D = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.w: J = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.q: H = None
        self.s: A = None
        self.t: H = None
        self.txt = txt

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

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