class A:
    def __init__(self, txt: str):
        self.o: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: A = None
        self.q: J = None
        self.p: F = None
        self.w: F = None
        self.u: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: G = None
        self.z: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: I = None
        self.s: G = None
        self.w: H = None
        self.v: H = None
        self.o: E = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.v: F = None
        self.u: B = None
        self.y: J = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.o: J = None
        self.w: D = None
        self.q: C = None
        self.p: J = None
        self.v: B = None
        self.txt = txt

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

m = A("m")
j = B("j")
n = C("n")
k = D("k")
h = E("h")
f = F("f")
g = G("g")
e = H("e")
l = I("l")
a = J("a")

m.o = n
j.v = m
j.q = a
j.p = f
j.w = f
j.u = l
n.w = g
n.z = f
k.x = l
k.s = g
k.w = e
k.v = e
k.o = h
h.z = g
f.t = g
f.x = n
g.v = f
g.u = j
g.y = a
e.x = j
e.w = j
e.z = j
e.q = k
e.y = k
e.p = f
e.u = a
e.o = m
e.s = h
l.o = a
l.p = a
l.w = k
l.q = n
l.v = j
a.s = k
a.x = f
a.z = j
a.w = j
a.u = g
a.q = g
a.t = g
a.v = n
a.o = n
a.p = h
assert g.v.t.y.s.s.u.q.txt == "
class A:
    def __init__(self, txt: str):
        self.o: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.v: A = None
        self.q: J = None
        self.p: F = None
        self.w: F = None
        self.u: I = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: G = None
        self.z: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.x: I = None
        self.s: G = None
        self.w: H = None
        self.v: H = None
        self.o: E = None
        self.txt = txt

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

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

class G:
    def __init__(self, txt: str):
        self.v: F = None
        self.u: B = None
        self.y: J = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.o: J = None
        self.w: D = None
        self.q: C = None
        self.p: J = None
        self.v: B = None
        self.txt = txt

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

m = A("m")
j = B("j")
n = C("n")
k = D("k")
h = E("h")
f = F("f")
g = G("g")
e = H("e")
l = I("l")
a = J("a")

m.o = n
j.v = m
j.q = a
j.p = f
j.w = f
j.u = l
n.w = g
n.z = f
k.x = l
k.s = g
k.w = e
k.v = e
k.o = h
h.z = g
f.t = g
f.x = n
g.v = f
g.u = j
g.y = a
e.x = j
e.w = j
e.z = j
e.q = k
e.y = k
e.p = f
e.u = a
e.o = m
e.s = h
l.o = a
l.p = a
l.w = k
l.q = n
l.v = j
a.s = k
a.x = f
a.z = j
a.w = j
a.u = g
a.q = g
a.t = g
a.v = n
a.o = n
a.p = h
assert g.v.t.y.s.s.u.q.txt == "a"