class A:
    def __init__(self, txt: str):
        self.y: F = None
        self.u: G = None
        self.o: F = None
        self.x: F = None
        self.r: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: F = None
        self.r: C = None
        self.p: G = None
        self.t: F = None
        self.x: A = None
        self.s: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.p: A = None
        self.s: D = None
        self.t: F = None
        self.y: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.w: C = None
        self.q: D = None
        self.y: F = None
        self.o: B = None
        self.x: D = None
        self.p: B = None
        self.r: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: A = None
        self.q: A = None
        self.r: G = None
        self.p: C = None
        self.t: E = None
        self.z: B = None
        self.y: G = None
        self.txt = txt

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

a = A("a")
i = B("i")
k = C("k")
d = D("d")
h = E("h")
g = F("g")
b = G("b")
l = D("l")

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

class B:
    def __init__(self, txt: str):
        self.q: F = None
        self.r: C = None
        self.p: G = None
        self.t: F = None
        self.x: A = None
        self.s: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.p: A = None
        self.s: D = None
        self.t: F = None
        self.y: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.w: C = None
        self.q: D = None
        self.y: F = None
        self.o: B = None
        self.x: D = None
        self.p: B = None
        self.r: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: A = None
        self.q: A = None
        self.r: G = None
        self.p: C = None
        self.t: E = None
        self.z: B = None
        self.y: G = None
        self.txt = txt

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

a = A("a")
i = B("i")
k = C("k")
d = D("d")
h = E("h")
g = F("g")
b = G("b")
l = D("l")

a.y = g
a.o = g
a.x = g
a.r = g
a.u = b
i.q = g
i.t = g
i.s = g
i.r = k
i.p = b
i.x = a
k.z = i
k.y = g
d.p = a
d.s = l
d.t = g
d.y = g
h.w = k
h.q = d
h.y = g
h.o = i
h.p = i
h.x = l
h.r = a
g.u = a
g.q = a
g.r = b
g.y = b
g.p = k
g.t = h
g.z = i
b.w = i
b.z = g
b.o = k
l.p = a
l.s = d
l.t = g
l.y = g
assert b.o.z.x.y.txt == "g"