class A:
    def __init__(self, txt: str):
        self.s: D = None
        self.t: G = None
        self.u: G = None
        self.txt = txt

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

class C:
    def __init__(self, txt: str):
        self.y: G = None
        self.s: F = None
        self.o: E = None
        self.q: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: B = None
        self.r: B = None
        self.y: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: C = None
        self.q: G = None
        self.z: G = None
        self.w: C = None
        self.t: A = None
        self.s: C = None
        self.o: B = None
        self.txt = txt

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

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

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

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

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

class C:
    def __init__(self, txt: str):
        self.y: G = None
        self.s: F = None
        self.o: E = None
        self.q: D = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.v: B = None
        self.r: B = None
        self.y: G = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: C = None
        self.q: G = None
        self.z: G = None
        self.w: C = None
        self.t: A = None
        self.s: C = None
        self.o: B = None
        self.txt = txt

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

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

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

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