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

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

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

class D:
    def __init__(self, txt: str):
        self.r: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: C = None
        self.v: A = None
        self.u: C = None
        self.q: G = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.q: A = None
        self.p: C = None
        self.z: C = None
        self.u: A = None
        self.s: D = None
        self.w: B = None
        self.txt = txt

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

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

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

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

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

class D:
    def __init__(self, txt: str):
        self.r: F = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.p: C = None
        self.v: A = None
        self.u: C = None
        self.q: G = None
        self.txt = txt

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

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

class H:
    def __init__(self, txt: str):
        self.q: A = None
        self.p: C = None
        self.z: C = None
        self.u: A = None
        self.s: D = None
        self.w: B = None
        self.txt = txt

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

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

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