class A:
    def __init__(self, txt: str):
        self.w: D = None
        self.z: G = None
        self.t: F = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.z: E = None
        self.q: F = None
        self.o: A = None
        self.u: E = None
        self.txt = txt

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

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

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

i = A("i")
h = B("h")
g = C("g")
e = D("e")
j = E("j")
k = F("k")
a = G("a")
n = E("n")

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

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

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

class D:
    def __init__(self, txt: str):
        self.z: E = None
        self.q: F = None
        self.o: A = None
        self.u: E = None
        self.txt = txt

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

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

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

i = A("i")
h = B("h")
g = C("g")
e = D("e")
j = E("j")
k = F("k")
a = G("a")
n = E("n")

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