class A:
    def __init__(self, txt: str):
        self.y: I = None
        self.z: I = None
        self.v: B = None
        self.o: C = None
        self.w: H = None
        self.p: G = None
        self.s: J = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.p: B = None
        self.t: A = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.q: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: C = None
        self.o: I = None
        self.v: A = None
        self.z: I = None
        self.x: D = None
        self.t: D = None
        self.p: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: A = None
        self.txt = txt

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

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

j.y = e
j.z = e
j.v = h
j.o = i
j.w = d
j.p = m
j.s = f
h.r = c
h.x = c
h.w = d
h.v = f
h.s = f
h.p = f
h.o = e
h.z = a
h.t = a
h.q = j
i.p = h
i.t = j
l.v = i
a.y = i
a.o = i
a.v = i
a.z = d
a.p = d
a.t = d
a.q = h
a.x = h
a.s = f
c.p = e
c.z = h
c.t = m
m.q = j
d.s = i
d.o = e
d.z = e
d.p = e
d.v = j
d.x = l
d.t = l
e.w = j
f.x = l
f.t = c
assert j.p.q.p.q.o.txt == "
class A:
    def __init__(self, txt: str):
        self.y: I = None
        self.z: I = None
        self.v: B = None
        self.o: C = None
        self.w: H = None
        self.p: G = None
        self.s: J = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.p: B = None
        self.t: A = None
        self.txt = txt

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

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

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

class G:
    def __init__(self, txt: str):
        self.q: A = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.s: C = None
        self.o: I = None
        self.v: A = None
        self.z: I = None
        self.x: D = None
        self.t: D = None
        self.p: I = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.w: A = None
        self.txt = txt

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

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

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