class A:
    def __init__(self, txt: str):
        self.z: C = None
        self.x: D = None
        self.s: B = None
        self.t: C = None
        self.p: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: C = None
        self.r: B = None
        self.x: A = None
        self.z: A = None
        self.s: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.p: F = None
        self.u: D = None
        self.w: C = None
        self.x: B = None
        self.q: E = None
        self.t: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: D = None
        self.z: E = None
        self.x: B = None
        self.u: B = None
        self.q: E = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: E = None
        self.r: A = None
        self.t: C = None
        self.q: C = None
        self.x: C = None
        self.u: E = None
        self.txt = txt

k = A("k")
d = B("d")
b = C("b")
e = D("e")
n = E("n")
i = F("i")
j = E("j")
g = C("g")
l = B("l")
f = D("f")

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

class B:
    def __init__(self, txt: str):
        self.v: C = None
        self.r: B = None
        self.x: A = None
        self.z: A = None
        self.s: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.p: F = None
        self.u: D = None
        self.w: C = None
        self.x: B = None
        self.q: E = None
        self.t: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: D = None
        self.z: E = None
        self.x: B = None
        self.u: B = None
        self.q: E = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: E = None
        self.r: A = None
        self.t: C = None
        self.q: C = None
        self.x: C = None
        self.u: E = None
        self.txt = txt

k = A("k")
d = B("d")
b = C("b")
e = D("e")
n = E("n")
i = F("i")
j = E("j")
g = C("g")
l = B("l")
f = D("f")

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