class A:
    def __init__(self, txt: str):
        self.r: H = None
        self.y: C = None
        self.u: H = None
        self.q: D = None
        self.v: J = None
        self.txt = txt

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

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

class D:
    def __init__(self, txt: str):
        self.v: E = None
        self.x: F = None
        self.z: J = None
        self.s: F = None
        self.o: C = None
        self.y: I = None
        self.w: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: H = None
        self.u: I = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.o: E = None
        self.t: B = None
        self.w: H = None
        self.z: C = None
        self.u: H = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.r: C = None
        self.v: E = None
        self.w: E = None
        self.txt = txt

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.v: E = None
        self.x: F = None
        self.z: J = None
        self.s: F = None
        self.o: C = None
        self.y: I = None
        self.w: A = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.x: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.w: H = None
        self.u: I = None
        self.txt = txt

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

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

class I:
    def __init__(self, txt: str):
        self.o: E = None
        self.t: B = None
        self.w: H = None
        self.z: C = None
        self.u: H = None
        self.txt = txt

class J:
    def __init__(self, txt: str):
        self.r: C = None
        self.v: E = None
        self.w: E = None
        self.txt = txt

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

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