class A:
    def __init__(self, txt: str):
        self.s: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: C = None
        self.t: F = None
        self.p: E = None
        self.r: C = None
        self.o: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: H = None
        self.v: H = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.x: B = None
        self.u: A = None
        self.s: I = None
        self.y: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: I = None
        self.x: B = None
        self.u: I = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.u: E = None
        self.t: H = None
        self.q: H = None
        self.txt = txt

b = A("b")
j = B("j")
a = C("a")
m = D("m")
k = E("k")
f = F("f")
i = G("i")
d = H("d")
e = I("e")

b.s = a
j.y = a
j.r = a
j.t = f
j.o = f
j.p = k
a.t = i
a.r = k
m.o = d
m.v = d
k.z = j
k.v = j
k.q = j
k.s = a
k.p = f
k.t = b
f.x = j
f.u = b
f.s = e
f.y = k
i.o = e
i.u = e
i.x = j
d.x = m
d.v = m
d.r = m
d.o = a
e.u = k
e.t = d
e.q = d
assert a.r.p.u.s.t.u.u.q.txt == "
class A:
    def __init__(self, txt: str):
        self.s: C = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.y: C = None
        self.t: F = None
        self.p: E = None
        self.r: C = None
        self.o: F = None
        self.txt = txt

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

class D:
    def __init__(self, txt: str):
        self.o: H = None
        self.v: H = None
        self.txt = txt

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

class F:
    def __init__(self, txt: str):
        self.x: B = None
        self.u: A = None
        self.s: I = None
        self.y: E = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: I = None
        self.x: B = None
        self.u: I = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.u: E = None
        self.t: H = None
        self.q: H = None
        self.txt = txt

b = A("b")
j = B("j")
a = C("a")
m = D("m")
k = E("k")
f = F("f")
i = G("i")
d = H("d")
e = I("e")

b.s = a
j.y = a
j.r = a
j.t = f
j.o = f
j.p = k
a.t = i
a.r = k
m.o = d
m.v = d
k.z = j
k.v = j
k.q = j
k.s = a
k.p = f
k.t = b
f.x = j
f.u = b
f.s = e
f.y = k
i.o = e
i.u = e
i.x = j
d.x = m
d.v = m
d.r = m
d.o = a
e.u = k
e.t = d
e.q = d
assert a.r.p.u.s.t.u.u.q.txt == "j"