class A:
    def __init__(self, txt: str):
        self.z: B = None
        self.o: D = None
        self.t: I = None
        self.p: D = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: C = None
        self.w: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: G = None
        self.o: F = None
        self.y: H = None
        self.r: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: B = None
        self.y: H = None
        self.p: H = None
        self.o: B = None
        self.v: H = None
        self.r: I = None
        self.s: H = None
        self.z: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: I = None
        self.y: A = None
        self.t: B = None
        self.o: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: F = None
        self.x: J = None
        self.t: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.q: C = None
        self.r: D = None
        self.x: D = None
        self.v: D = None
        self.y: F = None
        self.z: D = None
        self.txt = txt

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

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

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

class B:
    def __init__(self, txt: str):
        self.v: C = None
        self.w: A = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.v: H = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.s: G = None
        self.o: F = None
        self.y: H = None
        self.r: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: B = None
        self.y: H = None
        self.p: H = None
        self.o: B = None
        self.v: H = None
        self.r: I = None
        self.s: H = None
        self.z: I = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.v: I = None
        self.y: A = None
        self.t: B = None
        self.o: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.y: F = None
        self.x: J = None
        self.t: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.q: C = None
        self.r: D = None
        self.x: D = None
        self.v: D = None
        self.y: F = None
        self.z: D = None
        self.txt = txt

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

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

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