class A:
    def __init__(self, txt: str):
        self.v: I = None
        self.u: J = None
        self.s: F = None
        self.y: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.q: H = None
        self.t: D = None
        self.z: A = None
        self.y: H = None
        self.x: H = None
        self.v: J = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: B = None
        self.x: B = None
        self.v: E = None
        self.p: J = None
        self.t: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: C = None
        self.r: I = None
        self.p: I = None
        self.q: C = None
        self.u: G = None
        self.o: C = None
        self.txt = txt

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.v: C = None
        self.t: A = None
        self.y: G = None
        self.o: F = None
        self.x: H = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.q: H = None
        self.t: D = None
        self.z: A = None
        self.y: H = None
        self.x: H = None
        self.v: J = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: B = None
        self.x: B = None
        self.v: E = None
        self.p: J = None
        self.t: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.z: C = None
        self.r: I = None
        self.p: I = None
        self.q: C = None
        self.u: G = None
        self.o: C = None
        self.txt = txt

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

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

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

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

class I:
    def __init__(self, txt: str):
        self.v: C = None
        self.t: A = None
        self.y: G = None
        self.o: F = None
        self.x: H = None
        self.txt = txt

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

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

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