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

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

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

class D:
    def __init__(self, txt: str):
        self.s: B = None
        self.y: F = None
        self.q: B = None
        self.r: F = None
        self.txt = txt

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

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.s: B = None
        self.y: F = None
        self.q: B = None
        self.r: F = None
        self.txt = txt

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

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

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

e.t = n
e.x = k
e.v = m
e.s = h
e.q = a
e.y = c
m.u = a
m.v = c
m.w = n
m.r = h
m.t = h
a.y = f
f.s = n
f.q = n
f.y = k
f.r = i
c.t = f
i.t = a
i.w = f
i.y = f
i.q = f
i.p = c
n.u = a
n.v = c
n.w = m
n.r = h
n.t = e
h.t = n
h.v = n
h.x = k
h.s = e
h.q = a
h.y = c
j.y = f
k.t = j
k.w = f
k.y = f
k.q = f
k.p = c
assert j.y.s.t.x.t.y.txt == "f"