class A:
    def __init__(self, txt: str):
        self.u: C = None
        self.w: F = None
        self.z: I = None
        self.x: I = None
        self.txt = txt

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

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

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

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.o: J = None
        self.p: B = None
        self.v: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.x: G = None
        self.v: G = None
        self.txt = txt

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

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

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

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

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

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.o: J = None
        self.p: B = None
        self.v: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.x: G = None
        self.v: G = None
        self.txt = txt

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

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