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

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

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

class D:
    def __init__(self, txt: str):
        self.p: F = None
        self.z: C = None
        self.y: F = None
        self.o: B = None
        self.x: G = None
        self.w: G = None
        self.v: B = None
        self.txt = txt

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

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

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

e = A("e")
k = B("k")
l = C("l")
f = D("f")
a = E("a")
d = F("d")
g = G("g")
h = F("h")
i = C("i")
b = B("b")

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

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

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

class D:
    def __init__(self, txt: str):
        self.p: F = None
        self.z: C = None
        self.y: F = None
        self.o: B = None
        self.x: G = None
        self.w: G = None
        self.v: B = None
        self.txt = txt

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

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

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

e = A("e")
k = B("k")
l = C("l")
f = D("f")
a = E("a")
d = F("d")
g = G("g")
h = F("h")
i = C("i")
b = B("b")

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