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

class B:
    def __init__(self, txt: str):
        self.q: A = None
        self.r: C = None
        self.p: F = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.p: C = None
        self.o: G = None
        self.t: D = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.p: D = None
        self.o: A = None
        self.x: I = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.v: B = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.q: A = None
        self.r: C = None
        self.p: F = None
        self.txt = txt

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

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

class E:
    def __init__(self, txt: str):
        self.p: C = None
        self.o: G = None
        self.t: D = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.p: D = None
        self.o: A = None
        self.x: I = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.v: B = None
        self.txt = txt

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

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

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