class A:
    def __init__(self, txt: str):
        self.v: E = None
        self.q: B = None
        self.p: F = None
        self.x: C = None
        self.r: B = None
        self.txt = txt

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.p: E = None
        self.o: F = None
        self.q: C = None
        self.s: A = None
        self.y: A = None
        self.v: C = None
        self.txt = txt

a = A("a")
f = B("f")
c = C("c")
g = D("g")
k = E("k")
b = F("b")
m = E("m")
e = C("e")
l = D("l")
i = F("i")

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.p: E = None
        self.o: F = None
        self.q: C = None
        self.s: A = None
        self.y: A = None
        self.v: C = None
        self.txt = txt

a = A("a")
f = B("f")
c = C("c")
g = D("g")
k = E("k")
b = F("b")
m = E("m")
e = C("e")
l = D("l")
i = F("i")

a.v = m
a.q = f
a.r = f
a.p = i
a.x = e
f.t = b
c.x = e
c.w = e
c.z = e
c.y = e
c.r = k
c.u = g
g.u = b
g.p = b
g.r = f
g.x = l
k.z = b
k.p = m
k.q = l
k.x = g
k.w = e
b.p = m
b.o = i
b.q = c
b.v = c
b.s = a
b.y = a
m.z = i
m.p = k
m.q = g
m.x = g
m.w = c
e.x = c
e.w = c
e.z = c
e.y = c
e.r = k
e.u = g
l.u = i
l.p = i
l.r = f
l.x = g
i.p = k
i.o = b
i.q = e
i.v = e
i.s = a
i.y = a
assert c.x.u.u.s.p.o.s.x.txt == "e"