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

class B:
    def __init__(self, txt: str):
        self.q: G = None
        self.o: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: H = None
        self.w: I = None
        self.y: I = None
        self.u: A = None
        self.z: H = None
        self.o: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: A = None
        self.y: F = None
        self.o: C = None
        self.s: J = None
        self.txt = txt

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.q: G = None
        self.r: F = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.q: G = None
        self.o: H = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: H = None
        self.w: I = None
        self.y: I = None
        self.u: A = None
        self.z: H = None
        self.o: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: A = None
        self.y: F = None
        self.o: C = None
        self.s: J = None
        self.txt = txt

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.q: G = None
        self.r: F = None
        self.txt = txt

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

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

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