class A:
    def __init__(self, txt: str):
        self.u: E = None
        self.t: J = None
        self.q: B = None
        self.r: B = None
        self.w: G = None
        self.x: D = None
        self.v: G = None
        self.o: C = None
        self.s: G = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.r: I = None
        self.x: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: H = None
        self.o: C = None
        self.z: H = None
        self.x: B = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.z: H = None
        self.o: B = None
        self.q: I = None
        self.s: A = None
        self.x: B = None
        self.t: J = None
        self.w: B = None
        self.y: E = None
        self.v: E = None
        self.p: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.z: E = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.t: E = None
        self.o: D = None
        self.r: C = None
        self.w: D = None
        self.x: H = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.r: I = None
        self.x: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: H = None
        self.o: C = None
        self.z: H = None
        self.x: B = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.z: H = None
        self.o: B = None
        self.q: I = None
        self.s: A = None
        self.x: B = None
        self.t: J = None
        self.w: B = None
        self.y: E = None
        self.v: E = None
        self.p: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.z: E = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.t: E = None
        self.o: D = None
        self.r: C = None
        self.w: D = None
        self.x: H = None
        self.txt = txt

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

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