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

class B:
    def __init__(self, txt: str):
        self.s: E = None
        self.w: F = None
        self.o: E = None
        self.r: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.r: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: G = None
        self.q: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: D = None
        self.p: A = None
        self.u: A = None
        self.y: E = None
        self.q: A = None
        self.r: C = None
        self.o: A = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.s: E = None
        self.w: F = None
        self.o: E = None
        self.r: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.r: E = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.u: G = None
        self.q: G = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.s: D = None
        self.p: A = None
        self.u: A = None
        self.y: E = None
        self.q: A = None
        self.r: C = None
        self.o: A = None
        self.txt = txt

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

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