class A:
    def __init__(self, txt: str):
        self.o: H = None
        self.s: H = None
        self.z: D = None
        self.y: C = None
        self.t: H = None
        self.q: F = None
        self.p: J = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: F = None
        self.x: F = None
        self.v: F = None
        self.u: A = None
        self.r: A = None
        self.s: G = None
        self.q: D = None
        self.o: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: E = None
        self.r: D = None
        self.v: F = None
        self.w: D = None
        self.p: B = None
        self.s: F = None
        self.x: I = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.o: C = None
        self.u: F = None
        self.v: G = None
        self.s: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: E = None
        self.v: I = None
        self.p: A = None
        self.u: D = None
        self.t: C = None
        self.r: B = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.p: B = None
        self.z: A = None
        self.x: F = None
        self.s: G = None
        self.v: J = None
        self.o: J = None
        self.y: F = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.z: A = None
        self.p: G = None
        self.w: G = None
        self.q: G = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.y: F = None
        self.x: F = None
        self.v: F = None
        self.u: A = None
        self.r: A = None
        self.s: G = None
        self.q: D = None
        self.o: G = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.u: E = None
        self.r: D = None
        self.v: F = None
        self.w: D = None
        self.p: B = None
        self.s: F = None
        self.x: I = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.o: C = None
        self.u: F = None
        self.v: G = None
        self.s: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: E = None
        self.v: I = None
        self.p: A = None
        self.u: D = None
        self.t: C = None
        self.r: B = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.p: B = None
        self.z: A = None
        self.x: F = None
        self.s: G = None
        self.v: J = None
        self.o: J = None
        self.y: F = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.z: A = None
        self.p: G = None
        self.w: G = None
        self.q: G = None
        self.txt = txt

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

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