class A:
    def __init__(self, txt: str):
        self.s: E = None
        self.r: H = None
        self.u: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: I = None
        self.p: I = None
        self.y: C = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.y: G = None
        self.q: J = None
        self.w: H = None
        self.s: J = None
        self.x: J = None
        self.t: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: I = None
        self.v: A = None
        self.p: F = None
        self.w: F = None
        self.q: C = None
        self.x: D = None
        self.r: D = None
        self.u: H = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.y: I = None
        self.o: E = None
        self.x: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.p: E = None
        self.o: B = None
        self.u: J = None
        self.v: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.x: D = None
        self.p: H = None
        self.u: D = None
        self.z: I = None
        self.o: B = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.x: I = None
        self.p: I = None
        self.y: C = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.y: G = None
        self.q: J = None
        self.w: H = None
        self.s: J = None
        self.x: J = None
        self.t: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.z: I = None
        self.v: A = None
        self.p: F = None
        self.w: F = None
        self.q: C = None
        self.x: D = None
        self.r: D = None
        self.u: H = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.y: I = None
        self.o: E = None
        self.x: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.p: E = None
        self.o: B = None
        self.u: J = None
        self.v: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.x: D = None
        self.p: H = None
        self.u: D = None
        self.z: I = None
        self.o: B = None
        self.txt = txt

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

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