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

class B:
    def __init__(self, txt: str):
        self.u: A = None
        self.w: A = None
        self.z: A = None
        self.q: D = None
        self.o: C = None
        self.t: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: A = None
        self.y: A = None
        self.q: F = None
        self.z: B = None
        self.u: A = None
        self.o: B = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: B = None
        self.o: B = None
        self.w: B = None
        self.txt = txt

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

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

l.o = m
l.t = j
l.u = j
l.w = c
l.q = e
l.v = n
j.u = b
j.z = b
j.w = l
j.q = n
j.t = n
j.o = e
i.v = l
i.y = l
i.u = l
i.q = m
i.z = j
i.o = k
n.u = j
c.t = j
c.w = j
c.o = k
m.z = d
m.t = l
m.u = e
m.x = j
b.o = m
b.t = j
b.w = c
b.q = e
b.u = k
b.v = n
e.v = l
e.y = l
e.u = l
e.q = m
e.z = k
e.o = k
k.u = b
k.w = b
k.z = l
k.q = n
k.t = n
k.o = i
d.t = k
d.o = j
d.w = j
assert l.o.z.t.txt == "
class A:
    def __init__(self, txt: str):
        self.o: F = None
        self.t: B = None
        self.w: E = None
        self.q: C = None
        self.u: B = None
        self.v: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: A = None
        self.w: A = None
        self.z: A = None
        self.q: D = None
        self.o: C = None
        self.t: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: A = None
        self.y: A = None
        self.q: F = None
        self.z: B = None
        self.u: A = None
        self.o: B = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: B = None
        self.o: B = None
        self.w: B = None
        self.txt = txt

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

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

l.o = m
l.t = j
l.u = j
l.w = c
l.q = e
l.v = n
j.u = b
j.z = b
j.w = l
j.q = n
j.t = n
j.o = e
i.v = l
i.y = l
i.u = l
i.q = m
i.z = j
i.o = k
n.u = j
c.t = j
c.w = j
c.o = k
m.z = d
m.t = l
m.u = e
m.x = j
b.o = m
b.t = j
b.w = c
b.q = e
b.u = k
b.v = n
e.v = l
e.y = l
e.u = l
e.q = m
e.z = k
e.o = k
k.u = b
k.w = b
k.z = l
k.q = n
k.t = n
k.o = i
d.t = k
d.o = j
d.w = j
assert l.o.z.t.txt == "k"