class A:
    def __init__(self, txt: str):
        self.w: E = None
        self.v: B = None
        self.p: E = None
        self.x: E = None
        self.z: E = None
        self.s: C = None
        self.q: E = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.y: B = None
        self.s: B = None
        self.r: B = None
        self.u: B = None
        self.z: B = None
        self.x: A = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.t: A = None
        self.o: B = None
        self.u: G = None
        self.v: D = None
        self.s: B = None
        self.q: B = None
        self.txt = txt

b = A("b")
j = B("j")
n = C("n")
m = D("m")
k = E("k")
i = F("i")
h = G("h")
a = C("a")
f = G("f")
d = F("d")

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

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

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

class D:
    def __init__(self, txt: str):
        self.y: B = None
        self.s: B = None
        self.r: B = None
        self.u: B = None
        self.z: B = None
        self.x: A = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.t: A = None
        self.o: B = None
        self.u: G = None
        self.v: D = None
        self.s: B = None
        self.q: B = None
        self.txt = txt

b = A("b")
j = B("j")
n = C("n")
m = D("m")
k = E("k")
i = F("i")
h = G("h")
a = C("a")
f = G("f")
d = F("d")

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