class A:
    def __init__(self, txt: str):
        self.z: I = None
        self.r: J = None
        self.q: H = None
        self.v: J = None
        self.x: H = None
        self.o: B = None
        self.t: J = None
        self.p: J = None
        self.y: F = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.u: J = None
        self.z: I = None
        self.s: H = None
        self.o: A = None
        self.y: E = None
        self.w: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: E = None
        self.u: J = None
        self.o: H = None
        self.s: G = None
        self.z: B = None
        self.q: F = None
        self.v: E = None
        self.p: G = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.z: H = None
        self.w: D = None
        self.p: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: J = None
        self.t: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: J = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.u: C = None
        self.r: I = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.u: J = None
        self.z: I = None
        self.s: H = None
        self.o: A = None
        self.y: E = None
        self.w: F = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: E = None
        self.u: J = None
        self.o: H = None
        self.s: G = None
        self.z: B = None
        self.q: F = None
        self.v: E = None
        self.p: G = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.z: H = None
        self.w: D = None
        self.p: D = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: J = None
        self.t: A = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: J = None
        self.txt = txt

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

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

class J:
    def __init__(self, txt: str):
        self.u: C = None
        self.r: I = None
        self.txt = txt

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

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