class A:
    def __init__(self, txt: str):
        self.x: I = None
        self.w: E = None
        self.o: C = None
        self.t: D = None
        self.p: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.z: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: J = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.q: J = None
        self.t: E = None
        self.s: I = None
        self.v: C = None
        self.p: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: B = None
        self.y: H = None
        self.u: I = None
        self.x: C = None
        self.q: H = None
        self.t: H = None
        self.w: B = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.t: C = None
        self.y: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: D = None
        self.x: B = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.v: A = None
        self.t: H = None
        self.q: H = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.z: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.t: J = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.q: J = None
        self.t: E = None
        self.s: I = None
        self.v: C = None
        self.p: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: B = None
        self.y: H = None
        self.u: I = None
        self.x: C = None
        self.q: H = None
        self.t: H = None
        self.w: B = None
        self.txt = txt

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

class G:
    def __init__(self, txt: str):
        self.t: C = None
        self.y: H = None
        self.txt = txt

class H:
    def __init__(self, txt: str):
        self.u: D = None
        self.x: B = None
        self.txt = txt

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

class J:
    def __init__(self, txt: str):
        self.v: A = None
        self.t: H = None
        self.q: H = None
        self.txt = txt

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

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