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

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

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

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

class E:
    def __init__(self, txt: str):
        self.x: D = None
        self.w: A = None
        self.v: D = None
        self.o: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: B = None
        self.u: A = None
        self.v: C = None
        self.w: E = None
        self.p: G = None
        self.y: E = None
        self.q: G = None
        self.txt = txt

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

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

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

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

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

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

class E:
    def __init__(self, txt: str):
        self.x: D = None
        self.w: A = None
        self.v: D = None
        self.o: A = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.t: B = None
        self.u: A = None
        self.v: C = None
        self.w: E = None
        self.p: G = None
        self.y: E = None
        self.q: G = None
        self.txt = txt

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

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

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