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

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

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

class D:
    def __init__(self, txt: str):
        self.s: A = None
        self.u: G = None
        self.q: H = None
        self.o: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: A = None
        self.q: H = None
        self.x: F = None
        self.v: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: D = None
        self.q: A = None
        self.s: B = None
        self.y: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: H = None
        self.x: C = None
        self.o: B = None
        self.s: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: D = None
        self.txt = txt

j = A("j")
i = B("i")
d = C("d")
c = D("c")
l = E("l")
b = F("b")
a = G("a")
e = H("e")

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

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

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

class D:
    def __init__(self, txt: str):
        self.s: A = None
        self.u: G = None
        self.q: H = None
        self.o: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.y: A = None
        self.q: H = None
        self.x: F = None
        self.v: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.r: D = None
        self.q: A = None
        self.s: B = None
        self.y: G = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.r: H = None
        self.x: C = None
        self.o: B = None
        self.s: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: D = None
        self.txt = txt

j = A("j")
i = B("i")
d = C("d")
c = D("c")
l = E("l")
b = F("b")
a = G("a")
e = H("e")

j.x = a
j.t = i
i.z = e
i.x = l
i.v = l
i.s = a
d.s = e
d.y = b
d.r = l
c.s = j
c.o = j
c.u = a
c.q = e
l.y = j
l.q = e
l.x = b
l.v = c
b.r = c
b.q = j
b.s = i
b.y = a
a.r = e
a.x = d
a.o = i
a.s = l
e.v = c
assert a.o.v.q.v.q.v.u.o.txt == "i"