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

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

class C:
    def __init__(self, txt: str):
        self.w: E = None
        self.r: J = None
        self.z: H = None
        self.s: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.q: D = None
        self.v: J = None
        self.w: J = None
        self.o: A = None
        self.s: H = None
        self.y: D = None
        self.t: D = None
        self.x: H = None
        self.r: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.w: E = None
        self.q: G = None
        self.r: G = None
        self.p: A = None
        self.x: E = None
        self.s: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.r: G = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.w: E = None
        self.r: J = None
        self.z: H = None
        self.s: F = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.q: D = None
        self.v: J = None
        self.w: J = None
        self.o: A = None
        self.s: H = None
        self.y: D = None
        self.t: D = None
        self.x: H = None
        self.r: F = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.s: C = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.w: E = None
        self.q: G = None
        self.r: G = None
        self.p: A = None
        self.x: E = None
        self.s: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.r: G = None
        self.txt = txt

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

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

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