class A:
    def __init__(self, txt: str):
        self.s: G = None
        self.y: C = None
        self.x: D = None
        self.o: I = None
        self.txt = txt

class B:
    def __init__(self, txt: str):
        self.p: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: B = None
        self.q: C = None
        self.w: E = None
        self.u: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: H = None
        self.o: B = None
        self.y: C = None
        self.q: A = None
        self.z: I = None
        self.t: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: G = None
        self.z: B = None
        self.r: G = None
        self.q: D = None
        self.s: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: D = None
        self.r: C = None
        self.z: B = None
        self.v: A = None
        self.x: F = None
        self.y: F = None
        self.p: I = None
        self.t: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.x: F = None
        self.txt = txt

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

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

class B:
    def __init__(self, txt: str):
        self.p: E = None
        self.txt = txt

class C:
    def __init__(self, txt: str):
        self.w: F = None
        self.txt = txt

class D:
    def __init__(self, txt: str):
        self.y: B = None
        self.q: C = None
        self.w: E = None
        self.u: H = None
        self.txt = txt

class E:
    def __init__(self, txt: str):
        self.v: H = None
        self.o: B = None
        self.y: C = None
        self.q: A = None
        self.z: I = None
        self.t: H = None
        self.txt = txt

class F:
    def __init__(self, txt: str):
        self.o: G = None
        self.z: B = None
        self.r: G = None
        self.q: D = None
        self.s: I = None
        self.txt = txt

class G:
    def __init__(self, txt: str):
        self.o: D = None
        self.r: C = None
        self.z: B = None
        self.v: A = None
        self.x: F = None
        self.y: F = None
        self.p: I = None
        self.t: H = None
        self.txt = txt

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

class I:
    def __init__(self, txt: str):
        self.x: F = None
        self.txt = txt

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

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