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

class B:
    def __init__(self, txt: str):
        self.x: D = None
        self.w: G = None
        self.y: E = None
        self.s: I = None
        self.t: G = None
        self.o: D = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.r: H = None
        self.v: C = None
        self.w: F = None
        self.p: C = None
        self.y: H = None
        self.q: G = None
        self.z: A = None
        self.o: I = None
        self.x: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: A = None
        self.t: B = None
        self.p: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: I = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.s: C = None
        self.w: C = None
        self.z: C = None
        self.u: A = None
        self.q: H = None
        self.y: E = None
        self.v: B = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.x: D = None
        self.w: G = None
        self.y: E = None
        self.s: I = None
        self.t: G = None
        self.o: D = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.r: H = None
        self.v: C = None
        self.w: F = None
        self.p: C = None
        self.y: H = None
        self.q: G = None
        self.z: A = None
        self.o: I = None
        self.x: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.z: A = None
        self.t: B = None
        self.p: C = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.w: I = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.s: C = None
        self.w: C = None
        self.z: C = None
        self.u: A = None
        self.q: H = None
        self.y: E = None
        self.v: B = None
        self.txt = txt

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

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