class A:
    def __init__(self, txt: str):
        self.x: I = None
        self.s: E = None
        self.v: E = None
        self.y: E = None
        self.q: C = None
        self.z: H = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.o: I = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.p: A = None
        self.t: F = None
        self.z: H = None
        self.s: I = None
        self.v: H = None
        self.y: J = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: B = None
        self.p: J = None
        self.t: J = None
        self.w: D = None
        self.z: E = None
        self.q: H = None
        self.r: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.u: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.p: A = None
        self.w: A = None
        self.z: D = None
        self.v: E = None
        self.q: G = None
        self.x: C = None
        self.y: D = None
        self.t: E = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.r: H = None
        self.p: A = None
        self.y: I = None
        self.w: A = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.o: I = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.p: A = None
        self.t: F = None
        self.z: H = None
        self.s: I = None
        self.v: H = None
        self.y: J = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: B = None
        self.p: J = None
        self.t: J = None
        self.w: D = None
        self.z: E = None
        self.q: H = None
        self.r: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.u: B = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.p: A = None
        self.w: A = None
        self.z: D = None
        self.v: E = None
        self.q: G = None
        self.x: C = None
        self.y: D = None
        self.t: E = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.r: H = None
        self.p: A = None
        self.y: I = None
        self.w: A = None
        self.txt = txt

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

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