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

class B:
    def __init__(self, txt: str):
        self.u: D = None
        self.q: A = None
        self.w: I = None
        self.p: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.o: H = None
        self.s: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: A = None
        self.t: J = None
        self.p: A = None
        self.s: A = None
        self.w: G = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.w: H = None
        self.v: I = None
        self.p: A = None
        self.u: J = None
        self.t: B = None
        self.z: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: J = None
        self.s: G = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.s: H = None
        self.q: G = None
        self.u: C = None
        self.t: E = None
        self.z: C = None
        self.v: H = None
        self.x: H = None
        self.txt = txt

j = A("j")
l = B("l")
k = C("k")
c = D("c")
e = E("e")
m = F("m")
d = G("d")
h = H("h")
f = I("f")
b = J("b")

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

class B:
    def __init__(self, txt: str):
        self.u: D = None
        self.q: A = None
        self.w: I = None
        self.p: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.o: H = None
        self.s: A = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: A = None
        self.t: J = None
        self.p: A = None
        self.s: A = None
        self.w: G = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.w: H = None
        self.v: I = None
        self.p: A = None
        self.u: J = None
        self.t: B = None
        self.z: F = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.v: J = None
        self.s: G = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.s: H = None
        self.q: G = None
        self.u: C = None
        self.t: E = None
        self.z: C = None
        self.v: H = None
        self.x: H = None
        self.txt = txt

j = A("j")
l = B("l")
k = C("k")
c = D("c")
e = E("e")
m = F("m")
d = G("d")
h = H("h")
f = I("f")
b = J("b")

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