class A:
    def __init__(self, txt: str):
        self.u: F = None
        self.y: C = None
        self.q: A = None
        self.r: F = None
        self.w: F = None
        self.t: F = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.q: A = None
        self.w: F = None
        self.u: C = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.o: A = None
        self.u: C = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.q: A = None
        self.w: F = None
        self.u: C = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.o: A = None
        self.u: C = None
        self.txt = txt

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

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