class A:
    def __init__(self, txt: str):
        self.v: C = None
        self.y: C = None
        self.t: D = None
        self.w: C = None
        self.p: C = None
        self.q: F = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.y: F = None
        self.w: D = None
        self.u: E = None
        self.z: A = None
        self.x: F = None
        self.txt = txt

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

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

b = A("b")
m = B("m")
k = C("k")
j = D("j")
f = E("f")
i = F("i")
h = D("h")
a = C("a")
d = A("d")
l = D("l")

b.v = a
b.y = a
b.t = l
b.w = k
b.p = k
b.q = i
m.r = j
m.z = k
k.q = m
k.v = d
k.w = f
k.t = f
j.y = i
j.x = i
j.w = l
j.u = f
j.z = b
f.z = m
f.w = m
f.x = m
f.v = h
f.u = h
i.r = m
i.w = f
i.y = f
i.z = j
i.p = b
h.y = i
h.x = i
h.w = j
h.u = f
h.z = b
a.q = m
a.v = b
a.w = f
a.t = f
d.v = k
d.p = k
d.y = a
d.w = a
d.t = j
d.q = i
l.y = i
l.x = i
l.w = h
l.u = f
l.z = b
assert d.y.v.q.z.w.u.txt == "
class A:
    def __init__(self, txt: str):
        self.v: C = None
        self.y: C = None
        self.t: D = None
        self.w: C = None
        self.p: C = None
        self.q: F = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.y: F = None
        self.w: D = None
        self.u: E = None
        self.z: A = None
        self.x: F = None
        self.txt = txt

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

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

b = A("b")
m = B("m")
k = C("k")
j = D("j")
f = E("f")
i = F("i")
h = D("h")
a = C("a")
d = A("d")
l = D("l")

b.v = a
b.y = a
b.t = l
b.w = k
b.p = k
b.q = i
m.r = j
m.z = k
k.q = m
k.v = d
k.w = f
k.t = f
j.y = i
j.x = i
j.w = l
j.u = f
j.z = b
f.z = m
f.w = m
f.x = m
f.v = h
f.u = h
i.r = m
i.w = f
i.y = f
i.z = j
i.p = b
h.y = i
h.x = i
h.w = j
h.u = f
h.z = b
a.q = m
a.v = b
a.w = f
a.t = f
d.v = k
d.p = k
d.y = a
d.w = a
d.t = j
d.q = i
l.y = i
l.x = i
l.w = h
l.u = f
l.z = b
assert d.y.v.q.z.w.u.txt == "f"