class A:
    def __init__(self, txt: str):
        self.x: E = None
        self.t: B = None
        self.u: E = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.o: B = None
        self.t: B = None
        self.y: B = None
        self.z: F = None
        self.s: A = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.w: C = None
        self.t: D = None
        self.x: A = None
        self.txt = txt

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.o: B = None
        self.t: B = None
        self.y: B = None
        self.z: F = None
        self.s: A = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.w: C = None
        self.t: D = None
        self.x: A = None
        self.txt = txt

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

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

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