class A:
    def __init__(self, txt: str):
        self.o: G = None
        self.v: E = None
        self.s: E = None
        self.t: H = None
        self.z: C = None
        self.txt = txt

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.r: G = None
        self.s: D = None
        self.v: E = None
        self.u: B = None
        self.t: A = None
        self.p: A = None
        self.x: E = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.t: H = None
        self.u: E = None
        self.z: G = None
        self.q: J = None
        self.v: F = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.r: F = None
        self.w: B = None
        self.v: D = None
        self.z: E = None
        self.txt = txt

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

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.r: G = None
        self.s: D = None
        self.v: E = None
        self.u: B = None
        self.t: A = None
        self.p: A = None
        self.x: E = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.t: H = None
        self.u: E = None
        self.z: G = None
        self.q: J = None
        self.v: F = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.r: F = None
        self.w: B = None
        self.v: D = None
        self.z: E = None
        self.txt = txt

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

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