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

class B:
    def __init__(self, txt: str):
        self.s: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: B = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.w: H = None
        self.r: H = None
        self.z: A = None
        self.x: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: D = None
        self.s: G = None
        self.o: D = None
        self.txt = txt

h = A("h")
n = B("n")
g = C("g")
c = D("c")
k = E("k")
f = F("f")
a = G("a")
b = H("b")
i = E("i")

h.y = i
h.t = a
h.o = a
h.w = f
h.p = c
h.s = g
h.x = g
n.s = a
g.s = n
c.y = h
k.s = a
k.r = a
k.y = c
k.z = n
k.x = i
k.w = g
k.o = f
f.w = b
f.r = b
f.z = h
f.x = c
a.o = b
b.u = c
b.o = c
b.s = a
i.s = a
i.r = a
i.y = c
i.z = n
i.x = k
i.w = g
i.o = f
assert g.s.s.o.o.y.t.txt == "
class A:
    def __init__(self, txt: str):
        self.y: E = None
        self.t: G = None
        self.w: F = None
        self.p: D = None
        self.o: G = None
        self.s: C = None
        self.x: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.s: B = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.w: H = None
        self.r: H = None
        self.z: A = None
        self.x: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: D = None
        self.s: G = None
        self.o: D = None
        self.txt = txt

h = A("h")
n = B("n")
g = C("g")
c = D("c")
k = E("k")
f = F("f")
a = G("a")
b = H("b")
i = E("i")

h.y = i
h.t = a
h.o = a
h.w = f
h.p = c
h.s = g
h.x = g
n.s = a
g.s = n
c.y = h
k.s = a
k.r = a
k.y = c
k.z = n
k.x = i
k.w = g
k.o = f
f.w = b
f.r = b
f.z = h
f.x = c
a.o = b
b.u = c
b.o = c
b.s = a
i.s = a
i.r = a
i.y = c
i.z = n
i.x = k
i.w = g
i.o = f
assert g.s.s.o.o.y.t.txt == "a"