class A:
    def __init__(self, txt: str):
        self.y: G = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: F = None
        self.t: H = None
        self.s: E = None
        self.q: D = None
        self.o: F = None
        self.w: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: G = None
        self.o: E = None
        self.s: D = None
        self.y: G = None
        self.z: G = None
        self.v: B = None
        self.w: H = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.p: D = None
        self.o: C = None
        self.v: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: A = None
        self.z: G = None
        self.s: B = None
        self.r: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: B = None
        self.x: D = None
        self.t: F = None
        self.z: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: F = None
        self.s: F = None
        self.txt = txt

b = A("b")
d = B("d")
i = C("i")
n = D("n")
h = E("h")
e = F("e")
a = G("a")
c = H("c")
k = D("k")
j = C("j")

b.y = a
d.u = e
d.o = e
d.t = c
d.s = h
d.q = k
d.w = a
i.r = a
i.y = a
i.z = a
i.o = h
i.s = n
i.v = d
i.w = c
n.y = b
n.v = b
n.o = b
n.x = h
n.u = e
n.s = a
h.p = n
h.o = i
h.v = k
e.o = b
e.z = a
e.r = a
e.s = d
a.o = d
a.x = n
a.t = e
a.z = e
c.v = e
c.s = e
k.y = b
k.v = b
k.o = b
k.x = h
k.u = e
k.s = a
j.r = a
j.y = a
j.z = a
j.o = h
j.s = k
j.v = d
j.w = c
assert d.u.s.q.s.x.v.y.txt == "
class A:
    def __init__(self, txt: str):
        self.y: G = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: F = None
        self.t: H = None
        self.s: E = None
        self.q: D = None
        self.o: F = None
        self.w: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: G = None
        self.o: E = None
        self.s: D = None
        self.y: G = None
        self.z: G = None
        self.v: B = None
        self.w: H = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.p: D = None
        self.o: C = None
        self.v: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: A = None
        self.z: G = None
        self.s: B = None
        self.r: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: B = None
        self.x: D = None
        self.t: F = None
        self.z: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: F = None
        self.s: F = None
        self.txt = txt

b = A("b")
d = B("d")
i = C("i")
n = D("n")
h = E("h")
e = F("e")
a = G("a")
c = H("c")
k = D("k")
j = C("j")

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