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

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

class C:
    def __init__(self, txt: str):
        self.y: F = None
        self.w: B = None
        self.v: D = None
        self.o: D = None
        self.s: F = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.y: J = None
        self.s: I = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.r: J = None
        self.u: G = None
        self.o: J = None
        self.t: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.v: H = None
        self.o: G = None
        self.q: C = None
        self.txt = txt

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.y: F = None
        self.w: B = None
        self.v: D = None
        self.o: D = None
        self.s: F = None
        self.txt = txt

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

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

class F:
    def __init__(self, txt: str):
        self.y: J = None
        self.s: I = None
        self.txt = txt

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

class H:
    def __init__(self, txt: str):
        self.r: J = None
        self.u: G = None
        self.o: J = None
        self.t: D = None
        self.txt = txt

class I:
    def __init__(self, txt: str):
        self.v: H = None
        self.o: G = None
        self.q: C = None
        self.txt = txt

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

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

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