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

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

class C:
    def __init__(self, txt: str):
        self.q: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: C = None
        self.v: A = None
        self.p: A = None
        self.u: E = None
        self.r: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.u: A = None
        self.r: B = None
        self.w: B = None
        self.txt = txt

i = A("i")
k = B("k")
a = C("a")
n = D("n")
f = E("f")
h = F("h")
c = E("c")
b = A("b")
l = D("l")

i.x = b
i.s = l
i.w = h
i.u = h
i.q = k
k.r = c
k.t = l
a.q = f
n.z = a
n.v = b
n.p = b
n.u = f
n.r = k
f.z = k
f.v = k
f.t = k
f.x = l
f.o = h
f.u = h
h.u = i
h.r = k
h.w = k
c.z = k
c.v = k
c.t = k
c.x = l
c.o = h
c.u = h
b.x = i
b.s = l
b.w = h
b.u = h
b.q = k
l.z = a
l.v = i
l.p = i
l.u = c
l.r = k
assert b.s.z.q.x.r.t.r.txt == "
class A:
    def __init__(self, txt: str):
        self.x: A = None
        self.s: D = None
        self.w: F = None
        self.q: B = None
        self.u: F = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.q: E = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: C = None
        self.v: A = None
        self.p: A = None
        self.u: E = None
        self.r: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.u: A = None
        self.r: B = None
        self.w: B = None
        self.txt = txt

i = A("i")
k = B("k")
a = C("a")
n = D("n")
f = E("f")
h = F("h")
c = E("c")
b = A("b")
l = D("l")

i.x = b
i.s = l
i.w = h
i.u = h
i.q = k
k.r = c
k.t = l
a.q = f
n.z = a
n.v = b
n.p = b
n.u = f
n.r = k
f.z = k
f.v = k
f.t = k
f.x = l
f.o = h
f.u = h
h.u = i
h.r = k
h.w = k
c.z = k
c.v = k
c.t = k
c.x = l
c.o = h
c.u = h
b.x = i
b.s = l
b.w = h
b.u = h
b.q = k
l.z = a
l.v = i
l.p = i
l.u = c
l.r = k
assert b.s.z.q.x.r.t.r.txt == "k"