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

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

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.u: E = None
        self.o: B = None
        self.t: A = None
        self.x: H = None
        self.w: B = None
        self.q: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.o: B = None
        self.t: B = None
        self.s: F = None
        self.x: H = None
        self.p: G = None
        self.v: H = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.s: A = None
        self.v: H = None
        self.t: I = None
        self.q: C = None
        self.x: B = None
        self.r: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: D = None
        self.v: F = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.r: B = None
        self.v: H = None
        self.s: F = None
        self.u: A = None
        self.z: C = None
        self.y: D = None
        self.x: A = None
        self.txt = txt

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

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

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

class C:
    def __init__(self, txt: str):
        self.v: E = None
        self.u: E = None
        self.o: B = None
        self.t: A = None
        self.x: H = None
        self.w: B = None
        self.q: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.o: B = None
        self.t: B = None
        self.s: F = None
        self.x: H = None
        self.p: G = None
        self.v: H = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.s: A = None
        self.v: H = None
        self.t: I = None
        self.q: C = None
        self.x: B = None
        self.r: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.r: D = None
        self.v: F = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.r: B = None
        self.v: H = None
        self.s: F = None
        self.u: A = None
        self.z: C = None
        self.y: D = None
        self.x: A = None
        self.txt = txt

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

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