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

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

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

class D:
    def __init__(self, txt: str):
        self.r: B = None
        self.s: C = None
        self.w: G = None
        self.v: E = None
        self.t: I = None
        self.q: E = None
        self.p: H = None
        self.z: H = None
        self.txt = txt

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

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

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

class H:
    def __init__(self, txt: str):
        self.w: J = None
        self.x: I = None
        self.v: A = None
        self.q: J = None
        self.txt = txt

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

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

l = A("l")
i = B("i")
c = C("c")
d = D("d")
e = E("e")
k = F("k")
b = G("b")
f = H("f")
g = I("g")
j = J("j")

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

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

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

class D:
    def __init__(self, txt: str):
        self.r: B = None
        self.s: C = None
        self.w: G = None
        self.v: E = None
        self.t: I = None
        self.q: E = None
        self.p: H = None
        self.z: H = None
        self.txt = txt

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

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

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

class H:
    def __init__(self, txt: str):
        self.w: J = None
        self.x: I = None
        self.v: A = None
        self.q: J = None
        self.txt = txt

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

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

l = A("l")
i = B("i")
c = C("c")
d = D("d")
e = E("e")
k = F("k")
b = G("b")
f = H("f")
g = I("g")
j = J("j")

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