class A:
    def __init__(self, txt: str):
        self.s: E = None
        self.v: F = None
        self.p: B = None
        self.o: H = None
        self.txt = txt

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.p: H = None
        self.y: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: A = None
        self.s: C = None
        self.y: E = None
        self.t: A = None
        self.v: A = None
        self.q: F = None
        self.w: C = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.y: B = None
        self.o: B = None
        self.s: F = None
        self.u: H = None
        self.p: C = None
        self.t: F = None
        self.v: G = None
        self.r: G = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.s: E = None
        self.p: D = None
        self.y: E = None
        self.txt = txt

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

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

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

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

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

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

class F:
    def __init__(self, txt: str):
        self.p: H = None
        self.y: B = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: A = None
        self.s: C = None
        self.y: E = None
        self.t: A = None
        self.v: A = None
        self.q: F = None
        self.w: C = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.y: B = None
        self.o: B = None
        self.s: F = None
        self.u: H = None
        self.p: C = None
        self.t: F = None
        self.v: G = None
        self.r: G = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.s: E = None
        self.p: D = None
        self.y: E = None
        self.txt = txt

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

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