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

class B:
    def __init__(self, txt: str):
        self.y: D = None
        self.z: H = None
        self.v: H = None
        self.p: C = None
        self.u: A = None
        self.w: J = None
        self.t: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.o: D = None
        self.q: A = None
        self.w: D = None
        self.s: I = None
        self.x: H = None
        self.t: J = None
        self.z: F = None
        self.r: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: B = None
        self.y: F = None
        self.u: J = None
        self.o: H = None
        self.v: F = None
        self.p: A = None
        self.z: B = None
        self.r: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: G = None
        self.v: A = None
        self.y: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.t: F = None
        self.v: B = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.x: J = None
        self.y: B = None
        self.q: D = None
        self.s: C = None
        self.u: C = None
        self.z: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.z: E = None
        self.r: A = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.y: D = None
        self.z: H = None
        self.v: H = None
        self.p: C = None
        self.u: A = None
        self.w: J = None
        self.t: D = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.o: D = None
        self.q: A = None
        self.w: D = None
        self.s: I = None
        self.x: H = None
        self.t: J = None
        self.z: F = None
        self.r: B = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.w: B = None
        self.y: F = None
        self.u: J = None
        self.o: H = None
        self.v: F = None
        self.p: A = None
        self.z: B = None
        self.r: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.t: G = None
        self.v: A = None
        self.y: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.t: F = None
        self.v: B = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.x: J = None
        self.y: B = None
        self.q: D = None
        self.s: C = None
        self.u: C = None
        self.z: A = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.z: E = None
        self.r: A = None
        self.txt = txt

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

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