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

class B:
    def __init__(self, txt: str):
        self.s: C = None
        self.z: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: E = None
        self.t: A = None
        self.x: D = None
        self.r: H = None
        self.txt = txt

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

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

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

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

class H:
    def __init__(self, txt: str):
        self.t: A = None
        self.w: I = None
        self.p: B = None
        self.s: G = None
        self.u: B = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.u: C = None
        self.r: H = None
        self.x: I = None
        self.v: B = None
        self.txt = txt

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

c.o = h
c.v = h
c.q = b
c.z = b
c.s = b
c.t = i
c.w = j
c.y = a
h.s = a
h.z = e
a.y = e
a.t = c
a.x = n
a.r = g
n.v = c
n.w = i
n.y = a
n.p = a
n.u = a
n.x = a
n.z = f
n.s = e
n.t = b
e.y = g
e.r = g
e.t = b
e.w = c
e.q = f
e.z = n
e.s = h
f.u = e
f.s = e
f.x = i
f.q = j
f.p = j
f.t = h
f.y = h
f.v = n
f.o = a
f.r = c
b.x = f
b.v = i
b.o = i
b.p = i
b.z = j
b.s = a
b.y = a
b.q = e
g.t = c
g.w = i
g.p = h
g.u = h
g.s = b
i.u = n
i.v = a
i.x = a
i.y = f
i.z = f
i.p = e
i.s = g
i.q = b
i.r = b
i.t = h
j.u = a
j.r = g
j.x = i
j.v = h
assert b.q.w.t.txt == "
class A:
    def __init__(self, txt: str):
        self.o: B = None
        self.q: G = None
        self.t: I = None
        self.z: G = None
        self.v: B = None
        self.s: G = None
        self.w: J = None
        self.y: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: C = None
        self.z: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.y: E = None
        self.t: A = None
        self.x: D = None
        self.r: H = None
        self.txt = txt

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

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

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

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

class H:
    def __init__(self, txt: str):
        self.t: A = None
        self.w: I = None
        self.p: B = None
        self.s: G = None
        self.u: B = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.u: C = None
        self.r: H = None
        self.x: I = None
        self.v: B = None
        self.txt = txt

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

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