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

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

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

class D:
    def __init__(self, txt: str):
        self.x: C = None
        self.q: B = None
        self.u: G = None
        self.r: C = None
        self.t: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: E = None
        self.t: G = None
        self.z: B = None
        self.q: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: A = None
        self.o: C = None
        self.w: G = None
        self.q: F = None
        self.x: G = None
        self.t: C = None
        self.p: F = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: A = None
        self.v: D = None
        self.r: D = None
        self.z: C = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.x: C = None
        self.q: B = None
        self.u: G = None
        self.r: C = None
        self.t: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: E = None
        self.t: G = None
        self.z: B = None
        self.q: B = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: A = None
        self.o: C = None
        self.w: G = None
        self.q: F = None
        self.x: G = None
        self.t: C = None
        self.p: F = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: A = None
        self.v: D = None
        self.r: D = None
        self.z: C = None
        self.txt = txt

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

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