class A:
    def __init__(self, txt: str):
        self.s: J = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.t: E = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.s: H = None
        self.r: I = None
        self.z: D = None
        self.y: B = None
        self.v: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: G = None
        self.t: D = None
        self.x: D = None
        self.r: I = None
        self.u: H = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.q: J = None
        self.x: E = None
        self.s: C = None
        self.u: G = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.u: A = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.t: E = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.s: H = None
        self.r: I = None
        self.z: D = None
        self.y: B = None
        self.v: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: G = None
        self.t: D = None
        self.x: D = None
        self.r: I = None
        self.u: H = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.q: J = None
        self.x: E = None
        self.s: C = None
        self.u: G = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.u: A = None
        self.txt = txt

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

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