class A:
    def __init__(self, txt: str):
        self.o: F = None
        self.w: B = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.s: D = None
        self.u: G = None
        self.r: E = None
        self.w: F = None
        self.o: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: B = None
        self.y: G = None
        self.v: F = None
        self.s: G = None
        self.w: F = None
        self.z: A = None
        self.x: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.o: D = None
        self.z: F = None
        self.q: G = None
        self.p: C = None
        self.r: B = None
        self.t: C = None
        self.x: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: G = None
        self.t: B = None
        self.s: G = None
        self.o: G = None
        self.v: C = None
        self.q: G = None
        self.p: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: B = None
        self.r: C = None
        self.y: A = None
        self.q: D = None
        self.txt = txt

d = A("d")
l = B("l")
j = C("j")
h = D("h")
i = E("i")
e = F("e")
k = G("k")
f = D("f")
b = D("b")
c = E("c")

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

class B:
    def __init__(self, txt: str):
        self.s: D = None
        self.u: G = None
        self.r: E = None
        self.w: F = None
        self.o: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.r: B = None
        self.y: G = None
        self.v: F = None
        self.s: G = None
        self.w: F = None
        self.z: A = None
        self.x: A = None
        self.txt = txt

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

class E:
    def __init__(self, txt: str):
        self.o: D = None
        self.z: F = None
        self.q: G = None
        self.p: C = None
        self.r: B = None
        self.t: C = None
        self.x: C = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.u: G = None
        self.t: B = None
        self.s: G = None
        self.o: G = None
        self.v: C = None
        self.q: G = None
        self.p: D = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.p: B = None
        self.r: C = None
        self.y: A = None
        self.q: D = None
        self.txt = txt

d = A("d")
l = B("l")
j = C("j")
h = D("h")
i = E("i")
e = F("e")
k = G("k")
f = D("f")
b = D("b")
c = E("c")

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