class A:
    def __init__(self, txt: str):
        self.u: B = None
        self.p: D = None
        self.v: F = None
        self.y: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.p: H = None
        self.v: A = None
        self.s: J = None
        self.u: A = None
        self.z: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: D = None
        self.t: I = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.x: B = None
        self.w: H = None
        self.u: A = None
        self.t: C = None
        self.p: B = None
        self.q: G = None
        self.s: I = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.u: B = None
        self.o: C = None
        self.r: A = None
        self.p: H = None
        self.z: A = None
        self.w: J = None
        self.y: J = None
        self.x: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: E = None
        self.z: D = None
        self.txt = txt

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.p: H = None
        self.v: A = None
        self.s: J = None
        self.u: A = None
        self.z: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.p: D = None
        self.t: I = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.x: B = None
        self.w: H = None
        self.u: A = None
        self.t: C = None
        self.p: B = None
        self.q: G = None
        self.s: I = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.u: B = None
        self.o: C = None
        self.r: A = None
        self.p: H = None
        self.z: A = None
        self.w: J = None
        self.y: J = None
        self.x: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: E = None
        self.z: D = None
        self.txt = txt

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

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

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

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