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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.q: C = None
        self.v: C = None
        self.x: E = None
        self.p: C = None
        self.y: C = None
        self.u: D = None
        self.txt = txt

i = A("i")
g = B("g")
n = C("n")
h = D("h")
a = E("a")
e = F("e")
l = F("l")
m = F("m")
j = B("j")
f = C("f")

i.y = a
i.t = g
i.z = g
i.v = g
g.r = a
g.x = a
g.w = l
g.t = j
n.v = a
n.z = i
n.u = f
h.u = i
h.q = i
h.z = a
h.y = a
h.p = e
h.r = n
a.x = m
a.q = m
a.w = h
a.r = g
a.o = e
e.q = n
e.v = n
e.p = n
e.y = n
e.x = a
e.u = h
l.q = n
l.v = n
l.y = n
l.x = a
l.p = f
l.u = h
m.q = f
m.v = n
m.p = n
m.y = n
m.x = a
m.u = h
j.r = a
j.x = a
j.w = e
j.t = g
f.v = a
f.z = i
f.u = n
assert m.q.u.u.v.q.u.q.v.w.v.txt == "
class A:
    def __init__(self, txt: str):
        self.y: E = None
        self.t: B = None
        self.z: B = None
        self.v: B = None
        self.txt = txt

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.q: C = None
        self.v: C = None
        self.x: E = None
        self.p: C = None
        self.y: C = None
        self.u: D = None
        self.txt = txt

i = A("i")
g = B("g")
n = C("n")
h = D("h")
a = E("a")
e = F("e")
l = F("l")
m = F("m")
j = B("j")
f = C("f")

i.y = a
i.t = g
i.z = g
i.v = g
g.r = a
g.x = a
g.w = l
g.t = j
n.v = a
n.z = i
n.u = f
h.u = i
h.q = i
h.z = a
h.y = a
h.p = e
h.r = n
a.x = m
a.q = m
a.w = h
a.r = g
a.o = e
e.q = n
e.v = n
e.p = n
e.y = n
e.x = a
e.u = h
l.q = n
l.v = n
l.y = n
l.x = a
l.p = f
l.u = h
m.q = f
m.v = n
m.p = n
m.y = n
m.x = a
m.u = h
j.r = a
j.x = a
j.w = e
j.t = g
f.v = a
f.z = i
f.u = n
assert m.q.u.u.v.q.u.q.v.w.v.txt == "n"