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

class B:
    def __init__(self, txt: str):
        self.r: I = None
        self.t: H = None
        self.v: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: G = None
        self.w: G = None
        self.u: G = None
        self.y: B = None
        self.z: I = None
        self.q: H = None
        self.x: F = None
        self.v: F = None
        self.s: J = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.q: C = None
        self.o: A = None
        self.v: H = None
        self.r: C = None
        self.x: D = None
        self.txt = txt

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

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

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.r: I = None
        self.t: H = None
        self.v: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: G = None
        self.w: G = None
        self.u: G = None
        self.y: B = None
        self.z: I = None
        self.q: H = None
        self.x: F = None
        self.v: F = None
        self.s: J = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.q: C = None
        self.o: A = None
        self.v: H = None
        self.r: C = None
        self.x: D = None
        self.txt = txt

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

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

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

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

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

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

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