class A:
    def __init__(self, txt: str):
        self.r: G = None
        self.s: H = None
        self.y: B = None
        self.w: H = None
        self.x: E = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.p: J = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: J = None
        self.s: B = None
        self.y: I = None
        self.x: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: J = None
        self.y: C = None
        self.t: C = None
        self.s: D = None
        self.v: J = None
        self.p: J = None
        self.w: J = None
        self.z: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: B = None
        self.v: D = None
        self.p: B = None
        self.q: E = None
        self.w: I = None
        self.o: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: F = None
        self.q: J = None
        self.t: E = None
        self.r: D = None
        self.s: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: F = None
        self.z: G = None
        self.p: J = None
        self.r: D = None
        self.v: D = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.p: J = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.r: J = None
        self.s: B = None
        self.y: I = None
        self.x: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.r: J = None
        self.y: C = None
        self.t: C = None
        self.s: D = None
        self.v: J = None
        self.p: J = None
        self.w: J = None
        self.z: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.y: B = None
        self.v: D = None
        self.p: B = None
        self.q: E = None
        self.w: I = None
        self.o: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.v: E = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.p: F = None
        self.q: J = None
        self.t: E = None
        self.r: D = None
        self.s: F = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.s: F = None
        self.z: G = None
        self.p: J = None
        self.r: D = None
        self.v: D = None
        self.txt = txt

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

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

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