class A:
    def __init__(self, txt: str):
        self.y: D = None
        self.o: B = None
        self.s: A = None
        self.z: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: E = None
        self.v: A = None
        self.x: B = None
        self.s: F = None
        self.txt = txt

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

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.u: E = None
        self.v: A = None
        self.x: B = None
        self.s: F = None
        self.txt = txt

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

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

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

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

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

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