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

class B:
    def __init__(self, txt: str):
        self.s: C = None
        self.q: F = None
        self.o: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: D = None
        self.r: D = None
        self.t: D = None
        self.z: E = None
        self.o: B = None
        self.y: B = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: F = None
        self.w: B = None
        self.q: B = None
        self.z: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: B = None
        self.r: D = None
        self.txt = txt

i = A("i")
e = B("e")
h = C("h")
l = D("l")
b = E("b")
c = F("c")
d = E("d")

i.t = e
i.x = e
i.z = e
i.s = d
e.s = h
e.q = c
e.o = l
h.s = l
h.r = l
h.t = l
h.z = d
h.o = e
h.y = e
l.u = i
l.o = d
l.q = e
b.t = c
b.w = e
b.q = e
b.z = i
c.t = e
c.r = l
d.t = c
d.w = e
d.q = e
d.z = i
assert c.t.s.y.s.t.txt == "
class A:
    def __init__(self, txt: str):
        self.t: B = None
        self.s: E = None
        self.x: B = None
        self.z: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: C = None
        self.q: F = None
        self.o: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: D = None
        self.r: D = None
        self.t: D = None
        self.z: E = None
        self.o: B = None
        self.y: B = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: F = None
        self.w: B = None
        self.q: B = None
        self.z: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: B = None
        self.r: D = None
        self.txt = txt

i = A("i")
e = B("e")
h = C("h")
l = D("l")
b = E("b")
c = F("c")
d = E("d")

i.t = e
i.x = e
i.z = e
i.s = d
e.s = h
e.q = c
e.o = l
h.s = l
h.r = l
h.t = l
h.z = d
h.o = e
h.y = e
l.u = i
l.o = d
l.q = e
b.t = c
b.w = e
b.q = e
b.z = i
c.t = e
c.r = l
d.t = c
d.w = e
d.q = e
d.z = i
assert c.t.s.y.s.t.txt == "l"