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

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

class C:
    def __init__(self, txt: str):
        self.p: J = None
        self.s: D = None
        self.y: F = None
        self.u: J = None
        self.r: F = None
        self.z: J = None
        self.q: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: C = None
        self.o: B = None
        self.x: F = None
        self.u: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.w: A = None
        self.v: H = None
        self.o: E = None
        self.z: J = None
        self.r: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.u: J = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: F = None
        self.v: C = None
        self.r: G = None
        self.x: J = None
        self.t: F = None
        self.y: E = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.r: A = None
        self.x: I = None
        self.v: A = None
        self.y: B = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.p: J = None
        self.s: D = None
        self.y: F = None
        self.u: J = None
        self.r: F = None
        self.z: J = None
        self.q: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: C = None
        self.o: B = None
        self.x: F = None
        self.u: B = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.w: A = None
        self.v: H = None
        self.o: E = None
        self.z: J = None
        self.r: E = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.u: J = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.q: F = None
        self.v: C = None
        self.r: G = None
        self.x: J = None
        self.t: F = None
        self.y: E = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.r: A = None
        self.x: I = None
        self.v: A = None
        self.y: B = None
        self.txt = txt

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

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