class A:
    def __init__(self, txt: str):
        self.r: F = None
        self.w: B = None
        self.u: C = None
        self.x: E = None
        self.v: B = None
        self.y: G = None
        self.t: H = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: H = None
        self.p: J = None
        self.z: E = None
        self.q: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: A = None
        self.w: G = None
        self.t: H = None
        self.z: J = None
        self.u: F = None
        self.v: B = None
        self.p: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: B = None
        self.w: G = None
        self.t: D = None
        self.q: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: J = None
        self.v: J = None
        self.x: D = None
        self.s: B = None
        self.q: D = None
        self.p: H = None
        self.o: J = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: E = None
        self.z: D = None
        self.o: C = None
        self.w: A = None
        self.s: E = None
        self.t: D = None
        self.q: F = None
        self.p: C = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.v: G = None
        self.w: G = None
        self.o: C = None
        self.s: C = None
        self.p: B = None
        self.r: H = None
        self.z: F = None
        self.t: D = None
        self.x: F = None
        self.y: H = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.o: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: H = None
        self.p: J = None
        self.z: E = None
        self.q: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: A = None
        self.w: G = None
        self.t: H = None
        self.z: J = None
        self.u: F = None
        self.v: B = None
        self.p: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: B = None
        self.w: G = None
        self.t: D = None
        self.q: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: J = None
        self.v: J = None
        self.x: D = None
        self.s: B = None
        self.q: D = None
        self.p: H = None
        self.o: J = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: E = None
        self.z: D = None
        self.o: C = None
        self.w: A = None
        self.s: E = None
        self.t: D = None
        self.q: F = None
        self.p: C = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.v: G = None
        self.w: G = None
        self.o: C = None
        self.s: C = None
        self.p: B = None
        self.r: H = None
        self.z: F = None
        self.t: D = None
        self.x: F = None
        self.y: H = None
        self.txt = txt

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

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