class A:
    def __init__(self, txt: str):
        self.s: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.x: C = None
        self.w: A = None
        self.s: A = None
        self.y: F = None
        self.r: C = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.y: E = None
        self.s: G = None
        self.txt = txt

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

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

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

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

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

class B:
    def __init__(self, txt: str):
        self.x: C = None
        self.w: A = None
        self.s: A = None
        self.y: F = None
        self.r: C = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.y: E = None
        self.s: G = None
        self.txt = txt

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

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

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

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

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