class A:
    def __init__(self, txt: str):
        self.s: I = None
        self.t: I = None
        self.v: D = None
        self.x: F = None
        self.p: I = None
        self.z: D = None
        self.y: D = None
        self.r: E = None
        self.q: D = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.v: J = None
        self.o: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: G = None
        self.u: D = None
        self.z: F = None
        self.y: C = None
        self.s: F = None
        self.q: I = None
        self.p: B = None
        self.w: F = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.p: A = None
        self.w: C = None
        self.s: E = None
        self.x: A = None
        self.q: F = None
        self.t: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.x: C = None
        self.u: E = None
        self.r: C = None
        self.y: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.p: G = None
        self.x: D = None
        self.q: E = None
        self.v: B = None
        self.s: H = None
        self.z: A = None
        self.w: C = None
        self.o: B = None
        self.y: H = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.w: I = None
        self.u: B = None
        self.t: G = None
        self.p: I = None
        self.o: H = None
        self.s: H = None
        self.q: C = None
        self.v: A = None
        self.y: A = None
        self.x: F = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.v: J = None
        self.o: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.t: G = None
        self.u: D = None
        self.z: F = None
        self.y: C = None
        self.s: F = None
        self.q: I = None
        self.p: B = None
        self.w: F = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.p: A = None
        self.w: C = None
        self.s: E = None
        self.x: A = None
        self.q: F = None
        self.t: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.x: C = None
        self.u: E = None
        self.r: C = None
        self.y: G = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.p: G = None
        self.x: D = None
        self.q: E = None
        self.v: B = None
        self.s: H = None
        self.z: A = None
        self.w: C = None
        self.o: B = None
        self.y: H = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.w: I = None
        self.u: B = None
        self.t: G = None
        self.p: I = None
        self.o: H = None
        self.s: H = None
        self.q: C = None
        self.v: A = None
        self.y: A = None
        self.x: F = None
        self.txt = txt

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

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