class A:
    def __init__(self, txt: str):
        self.v: I = None
        self.p: I = None
        self.s: E = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.o: F = None
        self.y: A = None
        self.r: F = None
        self.w: J = None
        self.s: G = None
        self.v: J = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: B = None
        self.t: B = None
        self.p: B = None
        self.r: B = None
        self.v: J = None
        self.q: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: F = None
        self.x: H = None
        self.p: C = None
        self.w: J = None
        self.v: C = None
        self.q: A = None
        self.u: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: E = None
        self.t: G = None
        self.q: J = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: B = None
        self.s: B = None
        self.w: A = None
        self.u: C = None
        self.r: I = None
        self.y: J = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.p: B = None
        self.t: C = None
        self.o: D = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.y: I = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.o: F = None
        self.y: A = None
        self.r: F = None
        self.w: J = None
        self.s: G = None
        self.v: J = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: B = None
        self.t: B = None
        self.p: B = None
        self.r: B = None
        self.v: J = None
        self.q: C = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.s: F = None
        self.x: H = None
        self.p: C = None
        self.w: J = None
        self.v: C = None
        self.q: A = None
        self.u: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.x: E = None
        self.t: G = None
        self.q: J = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.z: B = None
        self.s: B = None
        self.w: A = None
        self.u: C = None
        self.r: I = None
        self.y: J = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.p: B = None
        self.t: C = None
        self.o: D = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.y: I = None
        self.txt = txt

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

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