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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.o: D = None
        self.r: E = None
        self.u: C = None
        self.p: A = None
        self.v: A = None
        self.t: I = None
        self.w: A = None
        self.s: C = None
        self.x: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: I = None
        self.o: A = None
        self.w: H = None
        self.u: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: D = None
        self.p: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: D = None
        self.u: G = None
        self.z: D = None
        self.s: G = None
        self.t: H = None
        self.q: E = None
        self.r: A = None
        self.txt = txt

a = A("a")
c = B("c")
k = C("k")
g = D("g")
l = E("l")
i = F("i")
e = G("e")
d = H("d")
b = I("b")
m = B("m")

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.o: D = None
        self.r: E = None
        self.u: C = None
        self.p: A = None
        self.v: A = None
        self.t: I = None
        self.w: A = None
        self.s: C = None
        self.x: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: I = None
        self.o: A = None
        self.w: H = None
        self.u: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: D = None
        self.p: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: D = None
        self.u: G = None
        self.z: D = None
        self.s: G = None
        self.t: H = None
        self.q: E = None
        self.r: A = None
        self.txt = txt

a = A("a")
c = B("c")
k = C("k")
g = D("g")
l = E("l")
i = F("i")
e = G("e")
d = H("d")
b = I("b")
m = B("m")

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