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

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

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

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

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

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

class G:
    def __init__(self, txt: str):
        self.r: D = None
        self.s: F = None
        self.x: E = None
        self.o: J = None
        self.v: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: B = None
        self.t: I = None
        self.v: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: E = None
        self.y: D = None
        self.s: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.y: C = None
        self.s: G = None
        self.w: F = None
        self.x: I = None
        self.p: B = None
        self.r: B = None
        self.txt = txt

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

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

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

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

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

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

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

class G:
    def __init__(self, txt: str):
        self.r: D = None
        self.s: F = None
        self.x: E = None
        self.o: J = None
        self.v: C = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: B = None
        self.t: I = None
        self.v: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.x: E = None
        self.y: D = None
        self.s: C = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.y: C = None
        self.s: G = None
        self.w: F = None
        self.x: I = None
        self.p: B = None
        self.r: B = None
        self.txt = txt

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

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