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

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

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

class D:
    def __init__(self, txt: str):
        self.x: A = None
        self.txt = txt

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

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

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

c.w = e
c.t = f
c.y = d
c.p = g
i.z = l
i.p = l
i.x = l
i.y = e
i.r = k
i.s = g
d.x = f
d.y = g
d.z = k
g.x = c
f.t = g
f.q = e
k.p = c
k.z = g
k.u = g
l.z = i
l.p = i
l.x = i
l.y = e
l.r = k
l.s = g
e.w = c
e.t = f
e.y = d
e.p = g
assert e.y.y.x.w.txt == "
class A:
    def __init__(self, txt: str):
        self.w: A = None
        self.t: E = None
        self.y: C = None
        self.p: D = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.x: A = None
        self.txt = txt

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

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

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

c.w = e
c.t = f
c.y = d
c.p = g
i.z = l
i.p = l
i.x = l
i.y = e
i.r = k
i.s = g
d.x = f
d.y = g
d.z = k
g.x = c
f.t = g
f.q = e
k.p = c
k.z = g
k.u = g
l.z = i
l.p = i
l.x = i
l.y = e
l.r = k
l.s = g
e.w = c
e.t = f
e.y = d
e.p = g
assert e.y.y.x.w.txt == "e"